Personal Identity and Brain Swapping

When last we left this perplexing topic, many of you were trying to get me arrested for a crime another I committed. (I say “many of you” even though only my mom and my lawyer were trying to do that, but my circle of friends has scant points about it, so ‘many’ it was.) When we are looking at memories as the signpost of identity-pointing, there are detours aplenty. Today, we are going to move on to the third of the potential candidates for identity fixing: the physical body.

Are You Your Body?

The pros and cons of the body as a candidate for personal identity here are pretty intuitive, and much of them we have seen earlier (with memories), if in slightly different form. The body is easily recognizable, and, in fact, is how we identify others. Slight changes, such as haircuts or tanning, seem to do little to distort or erase the recognizable features. However, which features matter the most? How many of them are necessary to maintain if one’s identity is to remain constant? Suppose you gain or lose three hundred pounds, you may well feel and be unrecognizable to both yourself and others. Are you a different person?Many soldiers are returning from Iraq and Afghanistan with missing limbs; are they different people? Both examples will result in the individual’s feeling different, but is that enough for identity to change as well? Think of the liquor store example from my previous post. How would that apply here?

Suppose that I rob the liquor store, but instead of getting hit by a car I instead cut off one of my arms.

Losing an arm

Is the the one-armed man the guilty person (I know Harrison Ford’s answer)?

What if I gain a lot of weight during the six weeks the police look for the robbing murderer?

Getting Fat

I doubt there is much controversy to either of these scenarios, and almost every one of you is going to think that identity has remained constant, that the same person is still there or here or whatever, even if that same person is not exactly the same (what’s the difference?, you might wonder, and good for you, you wondering person; the topic of identity when not dealing with people is going to be dealt with soon).

Remember when we talked about the Ship of Theseus, and I suggested that there are some who suggest that every possible change results in new identity. Such an individual, if she is consistent, would have to say that I am not the person who robbed the liquor store because I cut my fingernails or because I removed some hair. Such a person, though, is not really a person in the traditional sense of the word ‘person’, but is more of a collection of experiences that are joined together. Such a person cannot recall her first date, as all her recollections belong to someone else, just as such a person cannot look forward to a happier time in her life, as it will not be she that is enjoying that time, only someone who looks and thinks much as she does.

Few of you think like that, though. But why? If you are not in the memory camp and the physical features have changed beyond recognition, why is a person still the same even after extensive physical changes? What’s that? Sorry, the sound on my computer is muted — what are you saying at your screen as though Skype were on and our conversation was being passively monitored by virtuous government agencies? Ah, I see. Thoughts! The thoughts have not changed. Good! It’s almost as though you knew where I wanted this post to go. Thanks!

Thoughts and Brains

Of course, by ‘thoughts’ what your philosophically ignorant train of thinking was suggesting was the brain. What most members of the physical camp believe to be the defining feature of identity anchoring is the brain. So long as you have the same brain, you are the same person.

Another way to get to the brain is by elimination. Which parts of the body matter? For the body, that is pretty simple: beards, arms, legs, livers, ears, moles, etc., are all pretty superfluous. The part that matters is the brain. How much of the body matters? Really, again, almost all of the body is superfluous except the brain. What if the brain is damaged and the thoughts no more work good? Well, that is not the same brain then, is it? As far as which parts matter and how much of those parts matter, what am I, a brain scientist? (Yes. Yes, I am. Not in the United States, of course; regulations and all that have proven quite the obstacle to my life goals).

The solution to those worries is normally dealt with by a kind of common sense functionalism. Most of us don’t know Broca’s area from the pubic bone, but if you cannot remember anything from last night back, your brain… it don’t work too good. So the parts and amounts that matter for personal identity are the ones, whichever they are (and brain scientists know which those are), that affect the functioning of the brain.

Simple enough then. You are your functioning brain, and wherever it goes, so go you. Right? Right. Right? Well, dammit.

Swapping Brains

Let’s swap brains, then, you and I, and see where we go. Who wakes up in a svelte killing machine of evolutionary perfection and who wakes up in body aimed at child predation? No, no. There are no trick questions on this site. You will wake up, most of you think, in a body not originally yours. If the swap is permanent, maybe your personality will change based on how people around you treat you (either with sexual fearsomeness or with fear of your sexual perversity), but you are still basically the same person. You are your brain.

Note that this is different from those mind swap movies that are made every other week or so. In those instances, it is, or seems to be, the memories that are swapped and not the brains. A brain-based identity theorist watches those movies and laughs (partly at their sheer delightful hilarity) because the only change is that the individuals involved wrongly believe themselves to be someone else. How could they be, though, since their brains are still where they have always been?

There is really no way to confound anyone’s intuitions about the brain as it relates to identity, is there? Hahahahahahahahahahahahaha! Sorry, sorry — whoo, man. You really had there for a minute. Alright, let’s get to the confounding.

Suppose a man, let’s call him Gary, was born with half a brain. This happens, you know. Gary can still function and get about, but he only has half a brain. Maybe he cannot recall as much stuff as you can, maybe his motor skills are shaky in places, but he is a person and his name is Gary. Everyone okay with this?

Now let’s suppose that another person, Harry, has a regular, whole brain. But, egads! Harry is hit by a crazed Canadian driver and the resulting life-saving operation leaves him with half a brain. Now, this is not how it would work, but let’s suppose he still has around half his memories and the like. Is anyone here, aside from the identity-extremists, going to suggest that Harry is no longer Harry? Harry is still Harry even if only half of his brain is there since Harry can still function, to some degree, to some recognizable degree, as Harry used to.

Alright, and if we were to swap Harry’s half brain and Gary’s half brain, I suspect that you are going to think they, the people, go whither their brains do. Fine, fine. And if there was a third person, Terry, who lost his brain altogether, where is Terry? Gone. Right.

Brain swaps

What about this, though (and this is due to philosopher Derek Parfit): let’s take Gary’s half and Harry’s half and put them together into Terry’s head. Who is that? It has half of each person’s brain (well, I guess, it has all of their available brain, so whatever) and, so, we are suggesting here, it has half of each person’s memories, is it both Gary and Harry? If not, why not?

If Harry with a brain in his head was still Harry and not dead, then Harry’s half with Gary’s half should make them both be (please try not to laugh) who they once were. Can the one body be two persons? What if both Harry and Gary had had whole brains that we split, combining one half from each in two separate bodies? Can two bodies then be four persons? Oh, philosophy, what have you done to our so carefully coddled beliefs about all that is personally identical in the world?

Next Time…

Next time: clones! And light sabers! And sex!!! But mostly, and only, just clones.


Choosing a Kantian Maxim

Explaining anything about Immanuel Kant’s philosophy in a short blog post is a daunting and perhaps foolish task, but I am nothing if not undaunted and foolish.

I’d like here to address a particular problematic aspect of Kant’s ethical philosophy (and don’t let the terminology scare you off — it’s not as difficult as it’s about to sound): How one is supposed to go about applying Kant’s categorical imperative by way of universalizing a personal maxim?

Kant’s categorical imperative is the only pure (he had a thing about purity) moral law he could come up with, and it boils down to this: “Act only on that maxim by which you can at the same time will that it should become a universal law.” A maxim is a personal “ought” statement, like “I ought to save that puppy from that oncoming truck”. A universal law is generated from a maxim by applying it to the entire rational population. E.g., “Every rational person ought to save puppies from oncoming trucks.” And Kant’s categorical imperative asks us to use this process every time we wish to make an ethical choice: Come up with a personal maxim for the situation; universalize that maxim; and see if that universal law is something that should be followed by every rational person in every such situation.


Let’s go through an example of Kant’s process. Let’s say you’re faced with an instance where lying would be expedient. Here, then, is your personal maxim for the situation:

Maxim: I ought to lie in order to get out of a jam.

And then Kant asks you to universalize it:

Universal Law: Everyone ought to lie in order to get out of a jam.

According to Kant, this universalized version of your personal maxim shows us that your maxim is in fact immoral. Even though your maxim may seem harmless, and is certainly beneficial to you in the short term, by extending its reach to the whole of humanity, there arises something very bad. If we look at a world where everyone lies in every dicey situation, well, this is a world that is in trouble. And, thus, according to Kant, you should never lie. Period. No exceptions.

Lying to Nazis

This position leads to some obvious problems.

Say you’re in 1940 Germany, and you are harboring your Jewish neighbor in your attic, in order to protect her from the Nazis, who would like to find and kill her. Now imagine that the Nazis knock on your door and ask you: “Are you hiding any Jews in your attic? We’d like to kill them if you are.” The relevant moral question here, of course, is what do you do? Perhaps, as Kant thought, lying is a bad thing, but if you tell the truth in this situation, it will lead to your neighbor’s unwarranted death, which certainly seems worse, on the face of it.

Let’s look in a little detail at how Kant might have examined this situation. His logic went something like this:

  • If it’s okay for you to lie, then (according to the universalization of this maxim) it’s okay for everybody to lie.
  • But if everyone lies, then no one will ever believe anything anyone says.
  • And, thus, lies would become completely ineffectual.
  • Therefore, lying is a rationally inconsistent activity — it leads to its own conceptual destruction.

This rational inconsistency is at the heart of Kant’s claim that lying is immoral — he thinks that ethics has to be based on irrefutable, logical principles in order for it to be anything besides an argument over opinions. A concept that leads to its own self destruction certainly shows us that there is something inherently wrong with it. And so lying, in virtue of this, is immoral.

Choosing Your Maxim

But let’s look more closely at the procedure of picking your maxim in the lying example.

I should lie in order to help someone.

Is this a good candidate for a personal maxim? Well, no, not really. It’s certainly not generally applicable to moral situations. For instance, one could pretty easily argue that lying in order to help a mad bomber who is about to kill a thousand innocent people is probably not a very ethical thing to do.

I should lie in order to keep someone safe.

No, this has the same problem… what if you’re lying in order to keep the mad bomber from being arrested? This is arguably not a moral thing to do.

I should lie in order to save a life.

We’re getting better, but we still have the same problem lurking. If your lie is to save the life of an evil person, it’s at least arguable that the lie is not the morally right thing to do.

So let’s include something in our maxim to account for the idea that you are lying to protect someone innocent:

I should lie in order to save an innocent person from death at the hands of an evil person.

What happens if we universalize this maxim?

Everyone should always lie in order to save an innocent person from death at the hands of an evil person.

This is not bad, actually, but there’s still the Kantian objection of conceptual self-destruction lurking: If we always lie to evil people who want to kill innocent people, the evil people will start to catch on, and thus the lies will become self-defeating.

In fact, the example of lying is one of the best for Kant’s system — when he applies his system to other sorts of moral cases, it all starts to go to hell. But with lying, he has found a case where there is something internally irrational about the endeavor, when applied universally. But I’d like for a moment to talk about a general problem with Kant’s procedure. How, exactly, do you go about choosing your maxim?

The Problem of Specificity

One major problem here is that of specificity of the maxim you choose.

You could make your maxim very general:

I should lie to strangers.

This is just about the most general maxim you could use here; and certainly this isn’t universalizable. Not only would you not want to universalize it (everyone should lie to every stranger would be an odd moral rule!), but it harbors the same problem of lies being self-defeating.

What about if you go to the other extreme, and choose a very specific maxim?

I should lie in order to save the life of the Jewish person hiding in my attic in 1940 Germany from the Nazis who will kill her.

This is about as specific as you can get with your maxim. And actually this is pretty well universalizable, because by universalizing it you don’t lose much specificity — your universalized law is still quite specific and actually probably a good moral rule:

Everyone should lie in order to save the life of the Jewish person hiding in Alec’s attic in 1940 Germany from the Nazis who will kill her.

(You might generalize the universal law here a bit more: Everyone should lie in order to save the life of the Jewish person hiding in his or her own attic in 1940 Germany from the Nazis who will kill that Jewish person. Still, this is arguably easy to accept as a good universal law.)

The issue here is that very specific maxims will be easy to universalize, while very general ones won’t. And this is a problem because very specific maxims will usually be very uninteresting as the basis of moral tenets. Very general ones will usually be interesting.

Imagine instead of a moral law like “Murder is wrong”, we had a law that said “Murdering Joe Smith on August 24, 1968, because he applied the wrong postage to a letter, is wrong”. Other ethicists would mercilessly laugh us out of the business. Our law may be true, but is not very interesting.

So the only way to use Kant’s procedure to generate a sound moral rule is by picking a maxim that is so specific that it is morally mundane.

Other Problems With Kant

There are a million and one problems for Kantian ethics (although there are a million and two Kantian ethicists in the philosophical community today). But perhaps the most obvious concern with Kant’s ethics is that it doesn’t (in fact, explicitly so) account for the ends of one’s actions. Most of us are disposed to say that killing a mad bomber in order to save a thousand innocent lives is a moral action, regardless of the fact that it involves killing someone. Kant disagrees, saying we can’t rely on a good outcome (saving a thousand lives) as the basis of our ethics.

He’s got a point. What if you decide to kill the mad bomber, but by a fluke of luck you actually wind up wounding him instead, and he escapes, only to kill ten thousand people the next day? That fluke of luck turns you from a hero into a villain. This idea of moral luck is a fascinating topic on its own, but for our purposes here, it does cast Kant’s hardcore position in a somewhat better light. If good outcomes are dependent on luck, then perhaps a genuinely moral decision shouldn’t depend on its outcome — perhaps a good act is good no matter what the outcome.

Famously, a school of moral philosophy called utilitarianism (or more generally consequentialism) sprang up in direct opposition to this perspective. We’ll talk about some of its pluses and minuses in a future post.


Personal Identity and Lifetime Movies

My last post dealt with the Ship of Theseus. It was a kind of primer about personal identity. What you think about the ship, whether it was the same ship or not at the end of the journey, might reflect what you think about identity when it comes to individuals. If you thought the ship was different at the end of the journey, perhaps what matters to you are the physical parts of the body. If you thought that the ship was the same at the end of the journey, perhaps identity lies in something a bit more ephemeral. But what? Well, let’s see. And then let’s see why you’re wrong. (Alec is all about showing you what different people think; I am all about trying to get you to see what you think and why you are wrong for thinking so. That is why Alec gets more fan mail and I get more slashed tires.)

Personal identity has to do with what makes you who you are over time. There are three big common-sense solutions to the question of personal identity:

  1. The soul
  2. Memories/experiences
  3. The physical body

Let’s get rid of the soul right away. Whatever the hell you use to figure out who you are, it is a pretty safe bet that it is not the soul. That is not to say there is no such thing as a soul; maybe there is, and maybe there is not. You do not sense your soul in any sort of direct fashion, and so it is probably not what you use to determine your identity. Most of you who believe in a soul do so because of faith, not because of direct evidence. Is who you are based on faith as well? What if your soul left your body and another soul came in? Would you notice? How? I suspect that most of what believe the soul to be responsible for can be explained by the issues with the other two solutions, and since neither of them really work either, you shouldn’t sweat this one too much.

How about memories/experiences (that slash is going to be important in a later post, so don’t forget it)? If memories are what makes you who you are, what happens when you lose those memories? Suppose you get amnesia. Are you the same person you were before? Let’s just go right to a Lifetime Movie example to test intuitions (your intuitions, of course; mine are forged in the surly steel of philosophic uncertainty).

A woman is driving through, uh, let’s say northern Canada…

…and she loses control of her car, crashing into the Canadian forest.

In a dazed state, with a broken arm and minor head trauma, she wanders a bit until she comes upon a small town. She is quickly noticed and taken to the local medical clinic where they see to her wounds. Upon asking her who she is, where she is from, and if there is anyone they can call, the staff realize the woman has amnesia. Furthermore, she has no ID on her. Despite looking for many days, the townspeople have no luck finding out who she is or where she came from. Still, these are very nice, Canadian people, and so they ‘adopt’ her. She picks a new name, gets a job at the very hospital that helped patch her up, and then gets an apartment. She works there for a year or two, meets and then dates and then marries (awwwww…) a doctor. She is happy. This is Lifetime, though, so the good times only last about forty minutes or so into the tale.

She has been married, as the story goes, for five years, when one day she hears a knock on her door. Opening it, as she is now a trusting Canadian, she sees a man she does not recognize, and yet he seems to recognize her. “I’ve found you,” he says. “I’ve finally found you?”

“Who are you?” our plucky heroine asks.

“I’m your husband,” he says. And he has pictures to back this up: pictures of their wedding, her parents, her childhood, and so forth. She, of course, has no memory of him, her parents, or her childhood.

Now: philosophy!

Not to imply that marriage implies or entails (or anything else like those two) ownership, but this is just the easiest way to ask this question: Whose wife is she? The first guy or the second (current amnesiac state) guy? Keep in mind that we are not writing some sort of Lifetime Slash fiction here. She is probably not going to want to be with both. In fact, if asked, she expresses a clear preference for the second guy (since, you should recall, unless you are being ironic, she has no memory of the first guy).

I’ll have Alec set up some sort of poll for this question, but I am going to go ahead and forecast/predict that the majority of people are going to choose the second guy as the winner. But why, you might wonder, even those of you who agree but who have come to philosophy as a means to better elucidate your thoughts and opinions. Here is why: you believe that memories are what makes a person who she is. You are you because you remember doing the stuff you did. You do not remember all of it, but you think, and perhaps rightly, that you don’t need to. You do remember starting this article (it’s not that long yet, is it?); you remember eating dinner last night; you remember graduating from high school or junior high school or grade school (you preciously precocious bastard); and so on. What you do not remember doing, you common sensically believe you didn’t do. Maybe you are not always right (hey — that is a good topic for a later post! Thanks for that suggestion), but you still have that intuition. Our lovely Canadian is in the same memory leak of a boat. She recalls her current husband, but no other. Hence, she is only the woman she remembers being.

What happened, then, to the first husband’s wife? I suspect many of you are not comfortable with stating that she is dead, but then, where is she if she is not married to the second guy? Gone? Away? Buried deep in the mind of this new woman? Some of you are sure and some of you are not. Note that the answer here becomes murkier when we talk about her parents: did they lose their daughter as their son-in-law lost his wife? Physically no, but mentally yes? Are you comfortable with that? Would alcohol help?

Let’s change the example a bit, and then end this entry, giving you something to think on a bit or two. Suppose instead of a woman driving a car through the Canadian forest, it is me and I am at a liquor store. And instead of a car crash, I am buying a bottle of Maddog 20/20 (they all taste like gas, so let’s get the blue one because it is the prettiest). And instead of being found by benevolent Canadian townsfolk, I am shooting to death the liquor store operator, writing my name and social security number on the wall in his blood, leaving my driver’s license and hair and nail clippings in bag labeled “DNA” on the counter, and then walking outside yelling, “Hey, everyone! I just killed the liquor store operator of my own, sane volition!”

And then, instead of being given a job at a Canadian hospital, and falling in love with a lovely Canadian man, I am hit by a car (maybe driven by a Canadian), given severe head trauma, and awake in a hospital with permanent amnesia, having been arrested by the police who, given all the evidence I left behind, tracked me down in about five weeks.

With those slight and subtle changes in place, we can ask basically the same question we asked above: Is the person in the hospital bed the same as the the person who killed the liquor store operator? If you thought the woman was not the same as the one who had married the first guy in the first story, you should also think that the person in the bed is not the same guy as the one who killed the liquor store operator. And yet… And yet… You do. Why? Do you hate me? Are you sexist? Do you think that justice is more important than metaphysics (it isn’t)? Let’s end here and we will take this up and more in the next installment of: Do you know who I am? Who the hell are you?


Do Numbers Exist?

According to your disposition, you might have an immediate gut reaction to this question. My initial reaction (oh so long ago) was: “Of course numbers don’t exist. You can’t pick up the number 3 and throw it through a window.” That is, my intuition was that the only things that exist are the kinds of things that can be physically manipulated, and numbers, by almost every account, just aren’t this kind of thing.

To be clear about our terms, you can pick up numerals — that is, you can pick up concrete instances of numbers, like the plastic number signs at the gas station telling you how much gas costs, or the printed numerals in a book, denoting page numbers. But you don’t, by virtue of tearing out page three of a book and tossing it out a window, throw the number 3 out the window, any more than you throw me out of a window by drawing a picture of me and throwing that out the window.

Numbers, if they exist, are generally what philosophers call abstract objects, and those who maintain that such things exist claim that they exist outside of space and time. If you’re like me, you shake your head at such talk. “Outside of space and time? What does that even mean? Gibberish!” If you are similarly disposed, you might be a nominalist (in case you’re accumulating self-descriptive philosophical terms), and you are part of a long, proud philosophical tradition that thinks that existence is the exclusive domain of the physical.

However, your nominalism begins to run into problems pretty quickly. Never mind numbers. What about things like, say, novels? What exactly is the novel The Catcher in the Rye? It’s not any of the particular instantiations of it — it’s not the copy on your bookshelf; it’s not the copy on mine. All of the print copies on the planet could be eradicated and still the novel could be able to be said to exist. Is the novel the original manuscript sitting in a safe somewhere? But that could be burned and you could still argue that the novel exists. But if the novel itself is not identified with any of its particular instantiations, then the nominalist is in a bit of a quandary. On this perspective, the copies of the novel are instantiations of the novel itself, and the novel itself is seeming to be something abstract — something non-physical.

So the idea of something somehow existing outside space and time is suddenly not as absurd as it may have seemed. What about numbers, then? Of course there are disanalogies between numbers and novels. Novels are invented by humans, while, on most views of the subject, numbers exist whether or not humans ever happened to discover them. But, putting such differences aside for the moment, perhaps the existence of novels as abstract objects gives us some traction to say that numbers exist as abstract objects.

Abstract objects

What other sorts of things could be included in the category of abstract objects? The funny thing is that in many seminal texts on the subject, one has to plumb deep to find mention of what would count as an abstract object. Mathematical objects generally top the list (numbers, points, lines, triangles, etc.), followed by things like chess moves, games in general, pieces of music, and propositions. How are these things abstract? We generally think of a chess move, for instance, as something that exists by virtue of a concrete chess player actually moving a concrete chess piece in accordance with the rules of the game (which could themselves be considered abstract, but never mind this for the moment). But that seemingly concrete move can be instantiated in so many concrete ways — you could be replicating someone else’s game on your own chess board, you could make the move on a hundred different boards all at (nearly) the same time, you could make the move in your head before you make it on the board,… and all of these concrete possibilities point to the metaphysical problem here: If you believe there is only one move, and it’s concrete, then which move is the one move? And then what are the other moves? Copies of the move? Or instantiations of the same move? If you believe in abstract objects, you have, on some takes, an easier time of it. The move itself is an abstract object, and every physical version of that move is a concrete instantiation of that move. That is, none of the concrete, physical moves are actually the move — there is only one move and it is abstract, and any physical move is a copy, like a sculpture of a real person. (You can have a thousand sculptures of a person, but there’s only one person. The sculptures are imitations or instantiations of the person.)

This perspective is (loosely) called platonism, named after Plato’s idea that there are ideal “forms” — perfect archetypes of which objects in the real world are imperfect copies.

Why would these ideal forms not exist in space-time? I.e., why would they have to be abstract? Well, objects in space-time (the real world) are all imperfect copies of something. So if an ideal form existed in, say, your living room, then it would be non-ideal by virtue of existing in your living room. To put it perhaps less question-beggingly, if, say a chess move were instantiated in a thousand ways, how would you pick out the ideal version from which all others were copied? All of the instantiations would have similar properties, and so no one instantiation would stand out as different enough to count as the move, the platonic form of that move. Therefore, it makes sense to posit an abstract version of the move — something perfect, and outside of space-time, from which all the worldly versions are copied.

Thinking about geometric objects is perhaps the clearest way to think about abstract objects. A line segment (a true, geometric line segment) is a perfectly straight, one-dimensional object with a determinate length. There are no such objects in space-time. Every object you could possibly interact with is three-dimensional — no matter how thin a piece of, say, plastic you create, it always has a height and a thickness, giving it three dimensions. Nothing, therefore, in the concrete world, is a real geometric line segment. We have things that approximate line segments — very straight, very thin objects. But none of those things will ever be perfectly straight and with zero thickness. So if there does, somehow, exist a true line segment, it certainly isn’t in the concrete world, and therefore it must be in some sort of abstract realm.

Knowledge of abstract objects

One of the most damning aspects of platonism is its failure to come to terms with how we learn things about abstract objects. The general picture of how we acquire knowledge goes something like this: We perceive an object in the physical world, via physical means (e.g., light bounces off the physical object and hits our eyes), and eventually we process such perceptions in our brains and work with mental representations — i.e., brain states — of the object in question. But an abstract object can’t be processed like this. It is non-physical, and so, e.g., light can’t reflect off of it. So our usual causal theory of knowledge acquisition fails for things like numbers.

Well, then, how is it that we come across any knowledge of abstract objects, if they indeed exist? Some mathematical platonists, like the venerable logician Kurt Gödel, resorted to the idea that we just know truths about mathematical abstracta. As he wrote:

But, despite their remoteness from sense experience, we do have a perception also of the objects of set theory, as is seen from the fact that the axioms force themselves upon us as being true. I don’t see why we should have less confidence in this kind of perception, i.e., in mathematical intuition, than in sense perception…

But this is clearly an unacceptable answer to the problem of knowledge of abstract objects. How exactly do the axioms of set theory force themselves upon us? Waving your hands and saying “they just do” isn’t an account of the process, and leaves us in the dark as to how they just do, which is precisely what we need before we can take the platonist seriously as an epistemologist. (One need merely look at the history of geometry to see one serious problem with seeing the “obvious” truth of axioms. Until Lobachevsky and Riemann came along with consistent non-Euclidean geometries, nearly everyone though that Euclid’s fifth postulate “forced itself upon us”.) How does some feature of a non-spatiotemporal object force itself upon our spatiotemporal brains? The only way would be somewhat magical, and you could look to Descartes to see the folly of such a plan. Descartes posited that minds are distinct substances from brains, and indeed were non-spatiotemporally located. Of course, this leaves the problem of how the mind somehow slips into the brain and affects it. Descartes’ answer was that it crept in through the pineal gland. But this is no answer; it merely delays the answer for a moment. How does the non-spatiotemporal mind creep in through the pineal gland, and then into the brain? Descartes had no answer for this, of course, because the whole thing would be terribly mysterious, explaining how the non-physical interacts with the physical.

Worries like this keep nominalists well-motivated to stay on their side of the debate.

The argument from indispensability

Even if you’re dead-set against granting the existence of numbers, you think platonism is absurd, you have challenged platonism’s picture of knowledge, and you somehow have all of your nominalist ducks in a row, there is still one very influential argument to contend with as regards numbers’ existence: The argument from indispensability. Hardcore nominalists are often quite scientifically-minded, scientifically-motivated philosophers. And it is this love of science that gets them into trouble with denying the existence of numbers. The argument runs, in broad strokes, like this:

  1. Science is the best arbiter of what exists.
  2. Therefore, if science says something exists, we should accept it.
  3. Science relies (heavily and intractably) on mathematics.
  4. Therefore, science says that numbers exist.
  5. Therefore, numbers exist.

If you’re a good nominalist, you’re more than likely feeling obliged to accept this argument as sound. But if you accept its conclusion, then you’re right back to the issue of explaining what numbers are. They can’t be physical objects, therefore they must be abstract. But, as a nominalist you claim that there are no abstract objects! And you are caught in an intractable dilemma.

Many nominalists give up at this point. Hilary Putnam wrote resignedly:

Quantification over mathematical entities is indispensable for science…; but this commits us to accepting the existence of the mathematical entities in question. This type of argument stems, of course, from Quine, who has for years stressed both the indispensability of quantification over mathematical entities and the intellectual dishonesty of denying the existence of what one daily presupposes.

The talk of “quantification” is a bit of logic talk, but we can paraphrase it into regular English: “If science uses numbers, then science is committed to the existence of numbers.” You might see a glimmer of nominalist hope here. Science also uses frictionless planes, for example, and yet no scientist feels committed to the existence of those. Perhaps there is a way out of our commitment to numbers in the same way. Or perhaps, one might argue, frictionless planes actually do exist as platonic, abstract objects.

But there are two more “obvious” ways to be a nominalist about mathematics.

First, you could argue that numbers exist, and are actually physical objects. Penelope Maddy argues something close to this in her early work, Realism in Mathematics. She actually is here arguing for a version of naturalized platonism — the idea being that what is usually thought of as abstract objects are actually somehow existent in the physical world. But, platonist labels aside, the gain for nominalism on this take would be obvious: numbers, if they are physical objects, would be just another part of the down-to-earth nominalist physical world, like cats, trees, and quarks. This brave strategy, however, ultimately fails. It would take us into some metaphysical thickets to explain why, so I have relegated this to a paragraph at the very end of this post.

Second, you could argue that numbers aren’t actually indispensable to science. Hartry Field famously tried this strategy, claiming that science in fact only seems to rely on mathematics. On Field’s view, this seeming reliance is really just a fiction. In order to prove this Field attempted to nominalize a chunk of physics, by removing all reference to numbers within it. This complicated, counterintuitive project has met with equal parts awe and criticism. The consensus is that his project is untenable in the long term.

So do numbers exist or not?

Well, if you’re a platonist, you would answer “yes, numbers exist”. And further you would claim that they possess a sort of existence that is abstract — different from the sort of existence that stones, trees, and quarks enjoy. Of course, this means you are in the unenviable position of explaining the coherence of this sort of existence, along with the herculean task of explaining how we know about anything in this abstract, non-physical realm.

If you’re a nominalist, you’d probably answer “no, numbers do not exist”. However, now you have the unenviable job of explaining why mathematics seems so indispensable to science, while science is perhaps our best tool for saying which things exist. The two best nominalist answers to this conundrum seem untenable.

Probably, as is usually the case in philosophy, dogmatically sticking to one side of a two-sided debate will be inadequate. Maddy’s attempt at naturalizing platonism was a brave bridge across the nominalist-platonist divide, but clearly isn’t the right bridge. We’ll examine some other options in a future post.

References and Further Reading

Balaguer, Mark. (1998) Platonism and Anti-platonism in Mathematics. Oxford: Oxford University Press.

Benacerraf, Paul. (1973) “Mathematical Truth”, Journal of Philosophy 70.

Colyvan, Mark. (2001) The Indispensability of Mathematics. Oxford: Oxford University Press.

Irvine, A.D. (1990) Editor. Physicalism in Mathematics. Dordrecht: Kluwer.

Lowe, E. & Zalta, E. (1995) “Naturalized Platonism Versus Platonized Naturalism,” Journal of Philosophy 92.

Maddy, Penelope. (1992) Realism in Mathematics. Oxford: Clarendon Press. Revised paperback edition.

A note on Maddy’s naturalized platonism

Maddy actually thinks that we perceive sets. Number theory, as many logicians are proud to point out, can be reduced to set theory — i.e., numbers can be reduced to sets, which are, of course, generally seen as just another sort of abstract object. Maddy’s move is to bring those sets into the natural world. So that when we see an egg, we are perceiving that egg, but are also perceiving the set containing that egg. (A set containing an object is different from the object itself, you may recall from your math studies.) And that set containing the egg is a natural object, different from the egg itself. But now we run into trouble. Certainly there must be something different between an egg and a set containing that egg; otherwise ‘set containing that egg’ is just a proper name denoting the egg in question, and nothing metaphysical hangs on the distinction. (If you call me “Alec” or “author of this post”, you are not positing the existence of two people — these are just two different names for the same person.) Well, the usual distinguishing feature of abstracta is that they are not spatiotemporally located; but on Maddy’s scheme sets are spatial objects. The problem: Our egg and the set containing it necessarily co-exist in the same exact region of space-time, and yet they are supposed to be different things. In what does this difference consist? Well, certainly nothing physical, otherwise they wouldn’t co-exist in the exact same region of space-time. But then the difference must be something non-physical — i.e., something about the set must be abstract. And if this is the case, then we’re right back to all of the problems inherent in platonism, particularly the problem of how we can have any knowledge of such abstracta.


Identity and the Ship of Theseus

The Ship of Theseus is a great example of identity, though it does not work for everyone when it comes to personal identity, or the identity of people. Here is the basic idea. A guy named Theseus has a phenomenal ship that everyone wants, but he is not selling for any amount. However, one day, a merchant from a distant land offers Theseus an enormous sum to build an identical ship. The merchant wants the exact same sort of timbers from the same forest, the same nails from, uh, wherever the hell nails come from, the same sail material from the same cotton plants, and so on. If there is a plank of wood that has a knothole in it, the merchant wants an identical knothole in the same place on the duplicate ship. Sounds crazy, right? Well, most rich people are crazy. Theseus agrees and loads his ship with everything he needs to build a duplicate ship and then sets sail. He is only out of port for a couple of hours when one of the planks on his ship warps slightly and allows water into the ship. Theseus could return home and patch it, but he would just as soon get to the merchant, build the duplicate ship and then roll around on his big pile of money. With that in mind, he takes the corresponding piece, its identical counterpart, from the supplies and swaps the two planks out. (If you like, he makes a note of this switch, but his honesty does not matter for how the example works). As the journey continues, he needs to swap out more pieces: sail is torn, carpet is frayed, he needs a new wi-fi router, and so on. For ease of talking points, let’s make the following supposition: Once Theseus is 1/4 through his journey, he has 75% original parts and 25% new parts; at the 1/2 part, he has 50% original parts and 50% new parts; at the 3/4 mark, he has 25% original parts and 75% new parts; and finally, at the end of the journey, he has 0% original parts and 100% new parts.

Here’s the question: is the ship at the end of the voyage the same as the ship at the beginning of the journey? There are only two answers: yes, and no. A bunch of you are going to, somehow, try to wriggle more than that out of the situation, and your insane hearts are in the right place, but that will not make the insanity any less prevalent. Most of you are going to think the ship is not the same, so let’s talk about that first.

If the ship is different (and why wouldn’t be, you are collectively screaming), then when did it become different? At one point on the journey can we point at and say, “There! Did you see that? A different ship!” Here the answers are not so clear, but are not too difficult to lump together. Most people are in one of three categories: a) the very first change; b) right at or after the 50% mark; and c) the final change or replacement of parts. My question to all three groups is basically the same: why there? Why did you pick the percentage mark or the piece that you did?

The ship becomes a different ship at the very first change. This makes sense, I think, until you think about it and whether it makes sense. Suppose the very first change is a nail and not a piece of wood, does that matter? It shouldn’t. The percentage difference between a nail and a plank when the ship is taken as a whole is virtually negligible. What if a bird crapped on the ship? That is a change, but does it make for a different ship?

Of course, not. Bird crap is an extraneous feature of the ship, but is not integral to the identity of the ship itself “Integral”? Very impressive term! So if the ship loses a nail (one pops free), and that nail is not replaced, does that make for a different ship, Mr. Integral? Perhaps the nail was not an integral part, but then what is? If the sail is replaced, does that matter? What if only the hull is replaced? See, the problem is trying to figure out which parts are integral.

We often think of integral parts as though which cannot be taken away and the object still be whatever the hell it is. That can be due to reasons of either identity or function. If we take away the sail of the ship, it still floats and can haul freight (though it takes much longer), and I suspect none of us would have any issue with calling it the same ship. Is the same true if we took away only the hull? Not only would it look the same, but it is not going to float or hold any freight. So far, all of that is fairly intuitive. Let’s take away just the nails. The ship would probably fall apart very quickly, but until it does, is it the same ship? It looks that way and, at least for the moment, it functions in the same way.

Function As Identity
An issue with identity as function is this: Suppose we identify one another by function. First, how the hell do we ever figure out what our function is? If we are using it to fix identity, it cannot be something general like ‘reproduction’ or ‘making money’, because then how would we differentiate between individuals who are doing both or either? Let’s say that we resolve that issue, though, and fix your identity as ‘runner’ because that is what you do when you get any free time, or you are a competing runner or whatever. Dammit, just accept this as your function. Now, suppose you are hurt and can no longer use your legs, and so can no longer run. You can no longer perform the running function — what does that do to your identity? Is it gone? Is it changed?

More than half of the ship must change for the ship to be different: If one little change, even an little integral one, does not make for a different object, then what about a change of 51%? Again, the same questions can be asked: does it matter at all what that extra 1% change is?

Every single piece must change for the ship to be different: I won’t be petty and go rehash the above paragraph again (though I could, because it works). Let’s instead agree that the identity does not change until the last piece is swapped out. Does that make the last piece integral then? What if it is a nail instead of a plank? What if it is a stitch in the sail instead of a nail? Suppose we take that last piece out but do not replace it? 99% of the ship has been changed and the last one percent is just taken away, what does that mean for its identity? Yeah. I know.

Fine, then — the ship does not change. It is the same at the beginning as it is at the end. I can see, now, why you might think that. And everyone who originally thought it are now crowing to the moon about their daringly correct choice. Let’s suppose we now take all of the original parts and put them back together. It would be a fairly crappy ship, but why would that not be the original ship? Yeah. I know.

What you think about the Ship of Theseus might indicate what you think about identity for people. We will see as we continue on this topic in later (though soon upcoming) posts.


Trolley Problems

The so-called trolley problems form a set of ethical thought experiments meant to delve into our intuitions about killing, letting die, rights, and obligations.

Driver’s Two Options

The problems come in many forms, but here is the original version. There is a train (or trolley, but who the hell thinks about trolleys anymore) with failed brakes, about to barrel down upon and kill five unsuspecting rail workers. The driver can continue down this track, or steer to the right onto a spur where there is one unsuspecting rail worker awaiting certain doom. What should the driver do?

The intuition that is generally thought to be prompted by this is: the driver should steer to the right, killing one but saving five. It’s a numbers game wherein, other things being equal, one should kill as few people as possible. Killing one person, it is thought, is better (or less horrible) than killing five.

Of course, one may take issue with this intuition in any number of ways. For instance, there’s the “other things being equal” clause, which we’ll address shortly. (As a preview, imagine that the one worker is close to discovering a cure for cancer, and the five are shiftless hooligans. Perhaps in such a case the numbers game changes, and the utility of the one outweighs the utility of the five. More on this soon.) But to get at a more subtle problem with the case, let’s examine another trolley problem — one without any trolleys.

Judge’s Two Options

This time, imagine a judge faced with the following dilemma. A serial killer has been killing people for months, and everyone is getting understandably nervous. A vigilante group takes five innocent people hostage, and says to the judge: “if you don’t catch the killer and sentence him immediately to be executed, we will kill all five hostages.” The judge, not knowing who the killer is, has the following choice: do nothing and let the five innocent people die, or sacrifice an innocent person as a scapegoat to appease the vigilantes, thus killing one but saving five.

The intuition meant to be provoked here is that the judge has no moral right to sacrifice an innocent person’s life, regardless of any good consequences that act might have. So, in this case, as opposed to the initial trolley problem, the supposed moral is that it is not acceptable to save five by killing one.

So now we have two cases where killing one person would save five other lives, but in one case the killing of the one seems to be morally acceptable, and in the other the killing of the one seems to be morally unacceptable. What is the morally significant difference between these cases?

Killing versus Letting Die

Perhaps the difference is between killing and letting-die. In the case of the judge, she is not actually killing the five hostages (the vigilantes will do the killing), she is letting them die. If she were to sentence the one innocent person to execution, that would be much more of a case of direct killing. In the original trolley case, the driver has the choice between directly killing five or directly killing one. You might argue that faced with such a choice, the only morally significant factor is the numbers. But the judge is faced with a different situation, wherein she can either kill one or let five die. The numbers add up differently here, perhaps.

But perhaps not.

What happens if we eliminate the driver in the trolley case? Our train is driverless and brakeless, and barreling towards our five workers. A bystander is standing by a switch in the tracks, and can either do nothing, letting the five workers die, or throw the switch and send the train to the right, killing the one worker on the spur. What should the bystander do?

The intuition here is generally that the bystander should throw the switch and kill the one, saving the other five. But wait — our judge was supposed to let the five hostages die, so as to avoid killing one. Why is our bystander obligated to kill one in order to save five, when the circumstances seem so similar?

Well, you could argue that bystander’s case isn’t different at all from the judge’s case, and that, therefore he should not throw the switch. What if the bystander had three options: throw the switch one way and kill the one, do nothing and let the five die, or throw the switch the other way and kill himself.

Is the bystander morally obligated to throw the switch and kill himself? It would certainly be nice of him, but it would generally be regarded that this would be an act of a Super Samaritan, and that it would go above and beyond the normal obligations of morality. But if our bystander is not obligated to save five lives by sacrificing his own life, then perhaps he is not obligated to pay this price with someone else’s life. That is, perhaps the bystander in the two-options case should indeed, like the judge, let the five die, rather than sacrifice one in order to save five.

The Medicine

We’re getting further away from our initial reasoning in the first trolley case, in which we thought numbers were the primary factor. (I.e., if you have a choice between saving one life and saving five, you should generally choose to save five.) But now we’ve seen some cases in which we should choose to save one instead of five. Could it be that in general the numbers aren’t the relevant moral factor?

Here’s another trolley case to consider (another one without any trolley). Six people all need a special drug in order to live. You have enough to treat either one of the five (who needs all of the medicine you have), or to treat the other five (who each need a fifth or the medicine you have). What should you do?

This is another case that, on the face of it, harkens back to our original trolley case. It seems as if, everything else being equal, you should probably save the five instead of the one (let’s call the one “David”), because surely the numbers matter here. Of course, there could be special circumstances involved, and here we have to return to the “everything else being equal” clause that I promised to talk about earlier. Perhaps David has a far greater utility than the five — perhaps he is a cancer researcher, while the five are ne’er-do-wells. Or perhaps the five are all evil — murderers or nazis or CEOs or what have you — while David is a relatively good person. Or perhaps the five are all old and otherwise sick and fairly near death, while David is young and vibrant. Or perhaps there is a more hybrid socio-moral reason to choose to save David over the five: perhaps you are David’s parent, or David’s doctor, or you have signed a binding legal contract to give your medicine to David. These are all justifiable moral factors that break the “everything else being equal” clause here, and would morally allow you to give the medicine to David.

But what if you were simply David’s friend, and had no other reason to give him the medicine than that you want to. Would this make it into the list of justifiable moral reasons to save David instead of saving the five? Well, generally the intuition is that it is indeed not such a reason. You have no moral or contractual obligation to save David, you just want to save him. And generally this isn’t thought to be a good moral reason to act.

But maybe this is wrong. Suppose now that the drug is owned by David, not you. Would you try to persuade him to give his medicine to the five others? Should you? I should think not. David values his life more than the five strangers’ lives, and no amount of utilitarian mathematics would convince him otherwise (“come on, David — five lives are worth five times the value of your life, and so you should give the five your medicine…”). And David is certainly not violating anyone’s rights by keeping his own medicine — none of the five has any claim to the drug. It would be an act of supreme Samaritanism to give up his own medicine to save others.

But given this new analysis, perhaps in our previous case we were too hasty in throwing “I want to give David my medicine” into the category of morally unacceptable reasons. Perhaps valuing David’s life is a morally acceptable reason for saving his life to the detriment of five others. It is still the case that none of the five has any claim to the drug. (Nor does David, of course.) It’s my drug. But perhaps my valuing David’s life is enough to eclipse the concern about the numbers here.

What, then, about the original case where you have no special concerns for any of the parties involved? Perhaps the numbers still aren’t an important concern here. John Taurek (from whom I took this example) claims just this, and says we should simply flip a coin. Heads: we save David. Tails: we save the other five. This way, each of the five has a 50-50 chance of living. Taurek’s point is that we can’t measure the value of human lives — at least not in the way that we can measure the value of, say, jewelry. And so, left without this sort of measure, and without any other factors that would count towards breaking the “everything else being equal” deadlock (such as friendship), we should fall back to a random choice. Of course, like many philosophers, he goes a bit too far with his zealotry. He says there’s no difference in a case where you’d be weighing 50 lives against one; I suppose he’d go to the extent of saying there’s no difference in a case where you’d be weighing 5,000,000 lives against one, or 5,000,000,000 against one. But clearly this is just insanity. Just because you can’t weigh a human life’s value in the same way as a necklace’s doesn’t mean there’s no way to measure its value at all. And it certainly doesn’t mean that 5,000,000,000 lives can’t be seen as more valuable than one.


Perhaps the correct account of trolley cases must examine avoidability. Take for instance a new non-trolley trolley case: The Surgeon’s Two Options. A surgeon has six patients, five of whom will die very soon without various organ transplants, and one of whom has a broken toe but is otherwise vital and healthy. By an extreme coincidence, the patient with the broken toe has the exactly right blood and tissue types to match all of the five other patients, and thus would be as perfect a transplant match as could be without being a relative. The surgeon is thus presented with two choices: harvest the organs of the patient with the broken toe, and thus save the lives of the other five patients; or merely fix the patient’s toe and let the other five patients die.

In this case, if the surgeon harvests the organs, she has avoidably violated the rights of the patient with the broken toe. That is, she could have not taken the organs, and thus not violated the patient’s right to life, liberty, and the pursuit of metabolism.

In the original trolley case, whichever decision is made, someone will die. But it will be unavoidable. There’s nothing the driver could do to stop the killing. And if he decides to take the spur and kill the one worker instead of the five, there’s nothing about his decision that could have been impacted by the worker’s wishes. In the surgeon’s case, she could simply have asked the toe patient if he minded having his organs harvested, and the matter would have been perfectly clear.

On one reading of the surgeon’s case, the numbers don’t count, simply because rights are being avoidably violated. On a similar reading of the trolley case, the numbers do count, simply because there are no other morally relevant factors. (And, despite what Taurek claims, the numbers are indeed morally relevant.)

Killing versus Letting Die versus Withdrawing Aid

There’s one more thing we should look at regarding the killing versus letting-die discussion: namely, we have to consider a grey-area between them. Withdrawing aid. It will take us to an interesting place, in the end.

One take on the difference between killing and letting-die is that killing is an act of doing, and letting-die is an act of allowing. (You might have picked up on the strangeness of an act of allowing. That is, you might think these things reside in different metaphysical categories; i.e., you don’t act in order to allow something to happen — in fact, you have to not act in order to allow something to happen. But I think there’s an implicit action in deciding not to act. More on this, soon.) And if this is the proper analysis, then we can apply a similar analysis to the original trolley case and the surgeon’s two options. The driver could just stay on the main track, allowing the train to do what it would have done on its own; and this could be seen as an act of letting-die. If letting-die is a less serious moral offense than actively killing, then perhaps letting five die is still less egregious than killing one. In the case of the surgeon, we have the same issue: letting five die might be less morally egregious than killing one, and thus you’d have your moral decision.

But what about murkier cases of withdrawing aid? Take for example, this: You are swimming with a friend, and she starts to drown. You start to rescue her, but she is so scared and disoriented that she begins to pull you down with her. You realize that you will both die if you don’t disengage from your rescue attempt. You abort the attempt, and she dies. Did you kill your friend, or allow her to die? Well, you have certainly acted, by pushing your friend off of you, but is this really rising to the level of killing? Perhaps you want to say that your action was one of withdrawing aid, which you might well argue is less morally egregious than an act of killing.

We can fruitfully look here to Judith Jarvis Thomson’s famous thought experiment of the violinist. You have been kidnapped by a radical music-lovers group, and you wake up in a hospital bed next to a world-famous violinist. You are told that the violinist needs your kidneys in order to survive, and so has been hooked up to you while you were unconscious. The question is whether or not unhooking yourself from the violinist is murder. (The original case is meant to show us something about the ethics of abortion.) You might argue, as in the last example, that this is a case of withdrawing aid rather than that of outright killing the violinist.

What if, in a similar scenario, while you ponder what to do, the violinist’s arch-enemy sneaks into the room and disconnects you. This is withdrawing aid as much as the last case, but may strike you differently somehow. Is seems more like killing somehow than when you disconnect the violinist yourself.

My take is that these cases are both acts of killing. But when you disconnect yourself, it’s a justified killing. That is, you have rights that have been violated, and it is thus a right you have to disconnect yourself. That said, I think it’s still an act of killing — justified or not, we should call it what it is. The violinist’s enemy does not have the right to kill him, and so this is not a justified killing, though a killing it obviously still is.

The Proper Analysis

Is the trolley problem solvable in every variation via the same reasoning? I doubt it. Hundreds have tried, of course, and perusing the literature is a fascinating pastime for those who are curious. But I do think that, as in many of the cases above, the proper analysis will usually involve an examination of the rights involved, and that this will often take the moral high-ground above any arguments regarding killing, letting-die, or anything similar. We’ll take a closer look at rights-based systems of ethics in future posts.


McMahan, Jeff. (1993) “Killing, Letting Die, and Withdrawing Aid”. Ethics 103.

Naylor, Margery Bedford. (1988) “The Moral of the Trolley Problem”. Philosophy and Phenomenological Research 48.

Taurek, John. (1977) “Should the Numbers Count?” Philosophy & Public Affairs 6.

Thomson, Judith Jarvis. (1971) “A Defense of Abortion”. Philosophy & Public Affairs 1.

Thomson, Judith Jarvis. (2008) “Turning the Trolley”. Philosophy & Public Affairs 36.


Materialism and Doubt

A student emailed me asking me about the role of doubt in a materialist/science dominated culture. It was an excellent question. What role would doubt play in someone who believed that science could find all the answers? We do doubt, but the materialist is often portrayed as a person with a particular sort of confidence in her worldview. The materialist not only believes that everything that exists or could exist is physical, or physically based, but that all such things can be given fully physical explanations as well. While not all materialists do believe such a strong claim, enough do to lend strength to the stereotype.

I suggested to the student that doubt is what drives materialism, and that it is doubt that the materialist uses to suggest it is superior to dualism. What follows is how I tried to portray this to my student.


I think that most materialists would accept the description of them as ‘big bang until now’ kind of believers. There was the beginning, whatever that was (and whatever that was, it was entirely physical), and, given the laws of physics, everything has turned out as it has. That we are able to peer into the earliest times of the universe with our telescopes backs up this materialist perspective. It is, of course, possible that there are places or parts of the universe that are not bound by the laws of physics, but that seems less and less likely the more we learn about the universe.

What of doubt though, you ask? Is it evolutionarily beneficial? I have not read much on that issue specifically, but I have read quite a bit about it in a roundabout fashion. Here is what I think a materialist/scientist would suggest as the role and purpose, naturalistically speaking, of doubt. We are born not as blank slates, but as probability machines. What that means is that while we are not born with knowledge of how the world works, nor are we born with no rules or inclinations at all. Rather, we are born with a set of ingrained tools that allow us to figure out how the world seemingly works. Babies and children (and some adults), rarely take things at face value, despite appearances to the contrary. A child does not know how gravity works until it has seen many things fall (and many things, such as balloons and planes, not fall). The child is constantly touching and tasting and probing its way about and through the world to learn what the world is made of and how it works. But, one might say, that is curiosity, not doubt. I think that is right — at least, partially right.

Curiosity is the drive to learn, but the truly curious, which children are, do not merely accept what they encounter. They seek out not just new experiences, but the commonality that exists between and within those experiences. That means that, along with the curiosity, there is doubt present. There is doubt that what the child has just experienced is enough to understand, is correct, is the right sort of standard by which other experiences can be judged. We doubt, though not always (or even often) in the philosophical sense, because of its survival benefits. Should I trust that sound, just because it was trustworthy the first time I heard it? Should I believe that all red fruits are healthy and all blue breads are bad? Doubt drives curiosity drives doubt. If we did not doubt, the first suspected causal unions would have been good enough for us. A virgin in the volcano seems to have forestalled an eruption, therefore, the gods have been appeased. What need would we have of science if we had no doubt?

Curiosity is the desire to learn, but doubt is the tempering of what we have learned into knowledge. A creature that does not doubt will not survive long. And it is doubt that is built into science itself. The idea of falsifiability is based on doubt. If there is no way in which a theory could be shown to be false, it is not considered to be a good or strong theory. That is doubt.

While we are or can be 100% certain of how things seem to us on a sensory basis (I seem to be seeing green; I seem to be tasting an apple; I seem to be hearing crunching; etc.), often what we sense does not fit with what we have previously sensed or with what we currently believe. That is where the doubt comes in. Suppose I hear a voice telling me it is Volthoon and that I must kill my neighbors. I cannot doubt that it seems to me that I am hearing such a voice and that I am hearing it say such a thing, but I can doubt whether there is such a voice saying such things. Maybe I won’t question it (there are many who do not), or maybe I will not think to question it (there are many in this group as well), but I can certainly accept what I am sensing as something that I seem to be sensing without also accepting that it is a real and genuine thing that has not been concocted by my mind alone.

If I were to see a cat bark like a dog, it would confuse the hell out of me, not because I would doubt what I sensed, but because what I seemingly sensed did not fit in with any of my previous sensory experiences. Now I wonder which belief or set of beliefs I will have to drop or alter (and there comes doubt again). Now I wonder if I can trust my eyes or my ears (see the McGurk effect for a cool example of this), or neither or both. This doubt leads to the “why” question, I think, though you are entirely correct that it is a question that I may never be able to answer.

Final Thoughts

Doubt, unsurprisingly, is the philosopher’s bread and butter and beer and pillow. We all want to know what is going on, but we all want to be right. Those are desires that are at unfortunate odds with one another, but they are so because we doubt. I am not sure that the world is a better place because we doubt, but I am reasonably sure that we have survived as a species, and, less importantly, philosophy has thrived as a discipline, because we do.


What is True Depends on What is the Truth

This is a follow-up to Alec’s nicely written post on realism and its varieties. I put forth in the comments section the idea that what one believes to be the case with regards to realism v. anti-realism is going to color what one takes to be true in the world. Or, at the very least, what one considers to be a candidate of truth in the world. Here is why that is (and note that this is not merely my opinion, but is an established line of argument and belief among metaphysicians).

Realism, as Alec eloquently stated, is the view that the world is a particular way in a mind-independent fashion. Anti-realism is the view that the world is mind-dependent, and so derives many, perhaps all, of its features because of how it is perceived. Those are very quick takes on the two views and should not be satisfactory in and of themselves to anyone. Again, I refer you to Alec’s post.

Depending on which of the views you hold, your idea of what is true (or at least what you believe to be true) need not change, but what makes something true (its truth conditions) does change. Why might this be? First, let’s talk about the common sense view of truth.

Suppose a person makes the following utterance, “snow is white.” That utterance has a truth value. It is true if snow is white, and it is false if snow is any color other than white. How do we go about determining if it is true? Well, we go and look at snow. “Look”, you might say, if you live somewhere other than NYC or Chicago, “there is some snow, and it is white.” Hurray! We have verified its truth status. Or, dum dum dum, have we?

If you are a realist, you think that there are properties in the world that we can discover. This does not just mean that we can encounter snow, but that when we encounter snow, we can learn something about it, such as it being cold, malleable, crunchy, and white. If those are characteristics that we cannot discover or encounter, there is no way we can determine the truth value of any statements that make reference to such characteristics. The utterance, “snow is white”, is true only if snow is actually white. We laugh at a child who says, “snow is brown” because we know that snow is not brown (even in NYC, snow is white until it hits the dirty, dirty ground there). This is called the correspondence theory of truth. An utterance is true if it corresponds with what is actually the case in reality. “My keys are in the bowl by the door” is only true if my keys are in the bowl that is by the door. If they are in a dish, if they are in the kitchen, if I have no keys at all, the utterance is false because it does not correspond with how things actually are in reality. Hopefully you can see why a realist is drawn to the correspondence theory (though the two are not necessarily conjoined).

But I suspect you can also see why the anti-realist is not going to favor a correspondence theory of truth. For the anti-realist, most of what we believe to be the case about the world is due to how our minds project or create certain features or characteristics of what we perceive. For the anti-realist, the utterance of “snow is white” is expressing an opinion since there is no objective characteristic of ‘white’ in the world; there is only the experience that I refer to as ‘being white’. Whiteness, then, is a mind-dependent characteristic. It exists only because our minds create it. What does that do to the truth value of the utterance then? Well, as there is no objective reality to compare the utterance to, we cannot rely on the correspondence theory. Even if there were an actual characteristic of being white in the world, how could we ever know what that characteristic was like when our perceptions are so unreliable? And yet, the anti-realist does not want to say that there is no such thing as truth. Instead, what determines truth is something different from correspondence. It is called the coherence theory of truth. For the anti-realist (for many of them, at least), our mind-dependent experiences build up a large collection of beliefs about what we think the world is like. Since we cannot say what the world is actually like, we judge truth based on how well an utterance coheres (fits in) with our collection of beliefs. We want our collection of beliefs to be as coherent as possible. Note that coherence here does not merely mean understandable or rational, it means something larger: that our collection of beliefs not contain contradictions. We do not want to believe that we are both standing in the rain and we are not standing in the rain. We do not want to believe that snow is white together with snow is not white. (Of course, we can believe variations of those, but the contradictions are smoothed away by adding unspoken caveats to the utterance. For example, “snow is white” need not contradict “snow is not white” if we have the unspoken belief that the second utterance is about NYC snow which is changed or altered snow. “I am standing the rain” need not contradict “I am not standing in the rain” so long as we have the unspoken belief that I am standing beneath an umbrella which means that I am in the rain without being rained upon.)

Truth and Language
This can quickly become an issue of semantics or philosophy of language and so worth another, different post. Briefly, though, we know what we mean when we say what we do. When I point at snow and say, “snow is brown”, I do not literally mean that I believe snow is brown. Instead, I mean that snow, in such and such a state or condition (whatever condition is present, perhaps), is brown. If someone, maybe Alec, who knows, were to ask me, “do you mean to say that you think snow is brown?” I can honestly and reasonably say, “That is not what I meant when I said, ‘snow is brown.’ I meant that the snow here is brown, by which I meant to say, this is some really dirty snow.’” There is the demonstratrive sense of the utterance, by which I point and so indicate a particular batch of snow. Think of the old example about eskimos having eighteen different words for snow. That is a ridiculous example, I think, meant to suggest that eskimos like snow so much they talk about it a lot. But guess what? We non-eskimos have lots of different words for snow too: snow, wet snow, dry snow, soft snow, heavy snow, light snow, sleet, hail, etc. Wait a minute, you might exclaim, those are just the word ‘snow’ with an adjective in front of it. Yep — many of our words are like that. In fact, many words are like that: compound concepts captured in one word. What does ‘slush’ mean, if not icy rain? What is ‘beautiful’ aside from ‘pretty’ preceded by some number of ‘very’s?

Back to the topics at hand though, for an utterance to be true for the anti-realist, then, just means that the utterance fits in with my already accepted beliefs. “Snow is white” is true if what I call ‘snow’ is associated with the characteristic that I call ‘white’, and it means nothing beyond that. So, which theory of truth is correct? The realist theory is not correct, as there is no way to verify if what we have said actually corresponds with what is actually the case in the world. There is the experience I have whenever I come across a sensation that I label ‘white’, but why think that particular experience matches up with the way the world truly is? Perhaps I am color blind. Perhaps I am hallucinating. But you are not, the realist might contend. But how do you know that I am not? Can you prove that you are sensing the world as it actually is? If you could, there would be no anti-realist camp.

The anti-realist theory is not true either though, at least not obviously so. Coherence is an important attribute for any system of beliefs. For any system of beliefs, we want there to be as few outright contradictions as possible. Yet, why think that coherence alone is enough to establish truth? Someone who is schizophrenic or just simply insane might have a very coherent view of their experiences, but it only seems coherent to them because they are crazy. The schizophrenic person believes he hears voices separate from his own; he may even believe he sees people talking to him. We consider him sick though, because he is experiencing what no one else is or can. We say that the schizophrenic is wrong, not because his beliefs are not coherent, since many of them are (perhaps even as many of his beliefs cohere as do our own), but because he has beliefs that do not correspond to reality, to what we think is actually true. A claim, by the way, the schizophrenic will agree with once he is on successful medication.

What is the upshot of all this? Well, the realist maintains that our intuitive conception of truth is based on correspondence, not coherence, and the anti-realist maintains that we can never know whether our beliefs correspond with anything external to the mind, but that we can determine if our beliefs cohere with one another. Which you favor seemingly depends on what you think is real (though, to be fair, some suggest that what you think is real depends on what you think makes something true). However, it more often depends on what you think you justify as being true. That, however, has to do with straight up epistemology, and so must wait for another post.

Arguing Over Nothing

The Athletes-on-Steroids Debate

Arguing Over Nothing:A regular feature on the blog where we argue over something of little consequence, as if it were of major consequence. Arguing is philosophy’s raison d’être, and the beauty of an argument is often as much in its form as its content.Today, we argue about the acceptability of professional athletes using performance-enhancing steroids. Sides have been randomly assigned. Jim argues here for a pro-steroid position, while I take the con.

Each philosopher is granted up to a 500-750 words to state his/her case as well as up to 250-500 words for rebuttal. The winner will be decided by a poll of the readers (or whoever happens to have admin privileges at the appropriate time).

Jim: Arguing for the Use of Steroids

Really? I’ve been assigned the pro position? Dammit. Fine.

Before I present my arguments in favor of this very fine topic, I want to first lay out the purpose of the athlete, showing what I think the athletic endeavor is meant to display or do and what it is not meant for. Once that groundwork has been properly lain, my actual arguments will be easily to see and agree to.

Sports itself is merely a kind of communal physical activity, the doing of which I need not bother defending, as it is patently clear that nearly everyone (and my claim is not affected if ‘nearly everyone’ only picks out a bare majority) desires the company of others (while not every possible ‘other’, at least some people who are not oneself), and it is physically beneficial to take part in physical activities. Watching sports is another matter entirely, and it is here that the role of the professional athlete needs to be made clear.

One claim about athletes is that they show to the rest of us what the human body can do, what an object of grace and strength and fortitude can accomplish. I will not dispute that (though if the topic comes up later, I will be more than happy to give it a shot). I will claim that such displays are well handled by the amateur athletes — those who play college sports or in the olympics, or even in minor league sports. Such athletes are the ones who are competing for, among other things, the glory of the game or to personify the strength of the human spirit, and other such claims. The important aspect to note about such athletes (for the most part) is that they are not payed to play. They compete because of the joy and sense of accomplishment and what have you that they receive from the mere fact of competition. Our being allowed to watch such activities is enjoyable, but their purpose is not solely, I suggest, for our entertainment. Our entertainment is a by-product of their true purpose. Such is not so for the professional athlete.

The professional athlete exists to entertain us, the non-professional (perhaps even non-) athletes. The pro achieves remarkable things, often moreso than does the amateur, but professional accomplishments are the by-product of their athleticism — their purpose is to entertain, and any crossover into the realm of ‘attaining human perfection’ and the display thereof is but icing on the cake. We watch professional sports, if we do, because it entertains us. It entertains us with its athleticism, its drafting us into particular communities of comrades and opponents (our city/division/league is better than yours). We are happiest when our team wins, when we see events that we could not imagine happening otherwise, when we see records broken (records that mean nothing when not used to compare our team to that of another), when we see impressive feats of scoring or the prevention of which — we are happiest when we are entertained.

Professional athletes who take steroids are better capable of amazing physical performances than are those who do not. We watch professional sports because we want to be entertained by amazing physical performances. In fact, professional sports exists solely to provide such a venue. Therefore, athletes should be allowed to take steroids. They should be monitored to ensure they are as safe as possible, of course, but if steroids makes them better serve their purpose, then take them they should.

Alec: Arguing Against Steroid Use

First things first, the line between amateur and professional athlete is quickly evaporating, and we should reframe the argument appropriately. The Olympics, once the exclusive domain of amateur athletes, now allow professional athletes into the mix, because Olympic officials decided to let the best athletes in the world compete, not merely the poorest. There is also more parity than ever between professional and amateur athletes, in that college athletes are not only closer to professional level than ever before, but are also as equally involved in the entertainment aspect of the athletic industry. College football ad revenues in 2010 — for just the top 15 programs in the U.S. — topped a billion dollars.

So let’s dispense with the pro/amateur distinction. The bottom line is that athletes of any sort have two concerns: being the best they can be, and entertaining others. Even a middle-aged weekend warrior worries about looking good in front of the twenty people watching him play a very mediocre third base. The same warrior revels in the glory of an unusually graceful moment in the field. Alternately, the most jaded professional athlete can still revel in his athleticism even in the face of the realization that he is just there to make money. And obviously the professional has to worry about his entertainment value, even as he might be conflicted about it.

Now that the metaphysics are out of the way, we can analyze things more easily. The goals of being an athlete are two-fold (at least): being the best human specimen, and being the best entertainer. And this impacts the steroid debate in two ways.

Being the best human specimen. The key word here is, of course, “human”. What we (and the athletes in question) should be concerned with is developing the human body to its greatest potential. Once we start adding manufactured chemicals into the mix, we are getting into the realm of superhuman, or, perhaps more aptly hyperhuman. You will argue, no doubt, that athletes should be able to take, say, ibuprofen without being considered enhanced to an unnatural degree. And I agree. But surely also there is a line past which we cannot cross. By the time we get to adding bionic body parts to an athlete, we have certainly crossed that line. I argue that steroids have crossed that line as well.

Being the best entertainer. To some degree, it strikes me, no one cares (nor should they) what an entertainer does to enhance themselves for the benefit of the performance. But if we think about it for a moment, we might change our tune. Take, for instance, the extreme case of the singer who lip-syncs in concert. This is the ultimate enhancement to the singer’s biology. (Never mind that the enhancement is external to the singer. Picture a bodily embedded vocal track if it helps you.) But when we discover such an enhancement in practice, we become upset, and rightly so. We want to see live vocal feats — the human body stretched to its limits in a beautiful performance. We don’t want to hear prerecorded “perfection”, just because it’s possible. Similarly with athletes. When we find one cheating (corking a bat, taking steroids, doping), we are rightly dismayed. And this dismay is founded on the same basis of the previous paragraph. We want to see human-ness developed; not hyperhuman-ness.

Jim’s Reply to Alec

I will grant you the pro/amateur distinction is not a large one for this topic, but my so granting is due more to lack of space than to agreement. I will say this before moving on to the bulk of my reply: That various countries (America included) are now including professional athletes in the Olympics does not show a change in the inherent status of what an athlete is or is meant to be, it is instead a very successful attempt to move the Olympics from a showcase of Athletic achievement into something very much like a “our team is better than yours, so nah nah nah” mentality. The athletes that competed in the games were, for the most part, professional in the sense that they often only ever trained for the Olympics to the exclusion of anything else. Be that as it may, let’s move on.

Being the Best Human: This, I think, is, or is traditionally thought to be, the main purpose of the athlete. When we tend to think of the classical athlete, it is the Greek ideal we think of, and their supposed desire to reach perfection with the body. That desire was steeped in the idea of natural perfection, but why must we be trapped in such a conception? You mention a line we should not cross, but where we draw that line is arbitrary. Ibuprofen is allowed, but why? Because it is commonly used? That was not always the case — it only became so over time. Reconstructive knee surgery is not natural, is it? And yet it is quite common among athletes. Apparently taking steroids is the norm among bicyclists. Does that make it natural now? Otherwise, what is your definition of natural? It cannot be, or I suspect you do not want it to be, just whatever naturally (without our intervention) occurs in nature, so what else is it besides what is commonly accepted? Steroids in that latter sense were once unnatural, but are no longer so. Is constant excercise natural? Not in America. Does that disqualify athletes who work out in order to be better? You tell me.

Being the Best Entertainer: I wholeheartedly agree with you about singers being given false aid through the use of auto-tune or whatever the new audio enhancement is going to be called. Those are not biological enhancements though. There is nothing about that which I believe can properly be labeled as a human improvement. Steroids work on the muscles themselves, or so I gather; at the very least, they work on the body directly, and amplify its abilities to do more than what it can presently do. Auto-tune modifies a feature of the body that is separate from biology itself. It takes what the body does and works on it as a separate entity, treating it no differently than one might hair that one donates to a charity. Studio work modifies an entertainer no more than CGI does. Most of us know that we are not being entertained by a person, but by a computer’s rendering of some aspect of a person. Steroids do not make the body work differently — they make it work better (leaving open the meaning of ‘better’ here as something that is common sensical in the realm of sports).

Alec’s Reply to Jim

You have hoisted me by my own metaphysical petard! Well played! Indeed, the line to be drawn between acceptable and unacceptable performance aids is arbitrary. I was sort of hoping you’d miss that. Maybe, however, there’s a slender non-arbitrary thread at which to grasp here.

Ibuprofen doesn’t enhance one’s performance; it merely lets one perform through some minor discomfort. Reconstructive knee surgery doesn’t create a better knee than one originally had; it merely gets a knee back into useable form. These, I claim, fall safely on the acceptable side of the line separating acceptable from unacceptable. Steroids are meant not as an ameliorative nor as a repair, but explicitly as an enhancement to one’s otherwise natural ability. With steroids, one can be a better athlete. With, e.g., knee surgery, one can at best resume one’s career at the same level as previously.

Your example of constant exercise throws an undeniable wrench in my theory, however. Exercise is, clearly, meant to be something that improves one’s athleticism, and therefore could be seen as falling on the unacceptable side of my fine line. Yet obviously this is at best unintuitive and at worst a crushing blow to my theory. I admit that I have no unassailable defense against this. However, let me try one last maneuver. Let’s call “natural exercise” any form of exercise that one could undertake without advanced technology. Any form of running, stretching, weight-lifting, etc., would fall under this umbrella. (Never mind that most, e.g., modern weight machines are obviously technologically enhanced — someone with the appropriate set of rocks and sticks could emulate the majority of this technology.) Now let’s call “enhanced exercise” any form of exercise that relies inherently on technology. For instance, I’m imagining some sort of computer-aided analysis of muscle fibers during a workout, with an algorithm that instantaneously guides the athlete through electrical feedback into better postures. I claim that natural exercise is always acceptable, and enhanced exercise always unacceptable. And with this arguable line drawn anew, I rest my case. Tenuously.


What Is Realism?

Do you believe in the existence of stones, trees, cats, and the other everyday objects around us? It’s not a rhetorical question — there are actually philosophers who don’t believe in the existence of this sort of thing. What about the objects of mathematics? — numbers, abstract triangles, infinite quantities? How about the entities and laws of science? Or moral and aesthetic properties? What sorts of furniture are you willing to stow in the universe’s metaphysical attic?

Realism and Language
There is a school of thought that categorizes realism as a doctrine about truth and language instead of existence — the idea being that talking about the existence of sorts of things, and what it means for our talking to correspond to some sort of truth, is the real job of this branch of philosophy. This school of thought will be blatantly ignored by me in this piece, though those who are interested in finding out more can get lots of great references from Michael Devitt’s Realism and Truth.

Realism in philosophy is, broadly, a belief in the existence of some sorts of things. If you believe in the existence of numbers, you are a mathematical realist. If you believe in the existence of unobservable subatomic particles, you are a scientific realist. And so on, through the rest of the disciplines into which philosophy delves — ethics, aesthetics, language, and logic, to name a few.

Of course, just as there are realists about each of these sorts of things, there are also anti-realists — self-proclaimed disbelievers in the existence of those types of objects — and many a heated battle has been waged between the two camps in just about every arena.

Common-Sense Realism

What I’d like to talk about initially is realism (and anti-realism) about a sort of object that many of us take for granted as having an uncontroversial existence: stones, trees, and cats; the everyday objects of the external world. Let’s call this doctrine common-sense realism.

I said “external world” in the previous paragraph as a hat-tip to the debate that pretty much gave birth to the very notion of realism in the modern era: Cartesian skepticism. Rene Descartes, in his Meditations, pondered the objects about the existence of which he could be absolutely certain. In the end, he cast considerable and powerful doubt on the existence of even such mundane and seemingly certain things as stones, trees, and cats, saving his indubitable belief solely for the existence of his own mind. Descartes’ skepticism was so powerful, in fact, that it spawned an incredible genealogy of philosophers arguing about it for centuries to come. In the end, Descartes himself, with the generous and dubious help of his God, wound up believing in stones, trees, and cats, but other philosophers would not so easily shake off the doubts Descartes had raised. George Berkeley, for one, posited that, post-Descartes, it only made sense to believe in the existence of minds — not in the existence of stones, trees, and cats at all. (Stones, trees, and cats, on Berkeley’s take, are actually collections of ideas, which are, as ideas, completely dependent on minds for their existence.) So, thanks in part to Descartes, we have a divide that persists in our thinking about these things to this very day: there is the internal world (our minds) and the external world (stones, trees, and cats). Thanks to the certainty Descartes uncovered, almost no one until recently has been an anti-realist about minds; but many have been anti-realists about the external world.

So there are two facets to being a common-sense realist. It means, for one thing, that you believe in the existence of things like stones, trees, and cats; but for another thing, it means that you don’t think such things are dependent on minds for their existence. A tree, for a common-sense realist, is a real object in the real world, and would exist whether or not humans ever thought about it.

Mind Dependence
What sorts of things would be dependent for their existence on minds? Unless you are a disciple of Berkeley, this might be an odd question. But ponder things like dreams, emotions, and ideas. Clearly these sorts of things are mind-dependent. A stone, on the contrary, if you’re a common-sense realist, exists whether or not any minds exist. The fact that, e.g., dreams are mind-dependent puts them in an odd metaphysical category based on our criteria here. But we can put this to one side for the time being, noting that the fact that mind-dependent entities are mind-dependent is more of a boring truism than an earth-shaking metaphysical revelation.

So if you believe that stones, trees, and cats exist even when you’re not thinking about them, you are a common-sense realist. You might, naturally, be wondering why anyone would be an anti-realist about this sort of thing, or bout anything, for that matter. Well, actually, not a lot of philosophers since Berkeley are common-sense anti-realists. But anti-realism becomes a lot more attractive in other realms.

What other sorts of realism or anti-realism might you buy into?

Scientific Realism

If you’re a common-sense realist, you are also likely to be a scientific realist. Scientific realism is the doctrine that not only do stones, trees, and cats exist, but so do the objects that science posits. If you’re a scientific realist, you include amongst the furniture of your universe such so-called “unobservable” subatomic particles as electron, bosons, and quarks, as well as objects and phenomena on the other end of the magnitude spectrum such as black holes, gravity, and an expanding universe. One problem with scientific realism is that scientific theories are sometimes wrong, and so the objects that these theories posit can be fictional in the end. One favorite example in the literature is a 17th century theory of combustion that posited the existence of a substance called phlogiston. The theory, while scientifically accepted at the time, turned out to be wrong, and phlogiston was shown not to exist. So a 17th century scientific realist would have been put in the awkward position of believing in the reality of something that didn’t in fact exist.

How does a scientific realist come to grips with such uncertainty? Well, the general response from scientific realists is that this is the best we can do. Sure, science is sometimes wrong, but it’s still our best bet for uncovering the true nature of the universe. There is no non-scientific, privileged position from which we will ever be able to see the entire truth about the world — there is no window into the room that holds all of the furniture of the universe. Our current scientific theories provide the best view we can get.

Mathematical Realism

If you are a scientific realist, you might also be a mathematical realist, seeing how science and math seem to be so tightly bound together.

Actually, though I am a common-sense and scientific realist, my favorite brand of anti-realism is mathematical anti-realism. I have a hard time stomaching the idea of numbers and similar abstract objects existing independently of minds. I’m not alone in my distaste of mathematical realism, but those of us so disposed do face many issues — chief among them the seeming indispensability of math to science. If one is a scientific realist, and science relies indispensably on math, then on the face of it it seems as if one is committed to the existence of mathematical entities, whether or not one likes it. This indispensability argument has kept philosophers of math very busy over the last few decades.

For many of us on the anti-realist side of the mathematics debate, the big problem is that of causal inertness. Mathematical objects are, by consensus at any rate, abstract — that is, they take up no space and have no causal powers whatsoever. You can’t throw the number 8 through a window, for instance. And yet for a mathematical realist the number 8 still exists, somehow, and is indispensable to science. This sort of existence, for many of us, is just a completely different sort of thing from trees and quarks, which are just the sorts of things that can be thrown through windows. (Though you have to be pretty skilled to throw a quark anywhere.) For a mathematical anti-realist, it makes more sense to think of the number eight as a useful fiction; like Holden Caulfield with an advanced degree in particle physics.

Moral Realism

I’m probably the worst person to be writing about moral realism, because I never really understood what it was supposed to accomplish to posit actual entities/properties (philosophers talk more about moral properties than entities) of ethics. And yet, on certain takes, this is exactly what moral realism posits. At least mathematical entities are tightly bound to the entities of physics. Moral properties, if they were to exist, would be tightly bound to human psychology and systems of justice — both clearly dependent on human minds for their existence.

Mostly, the case for moral realism is stated in terms of semantics instead of existence — moral realists say that moral statements can be taken to be objectively true or false, in opposition to some common-sense intuitions that moral statements are subjective and/or dependent for their validity on the cultures in which they are uttered. But if “that cat is black” is a true statement because there is indeed a black cat in front of you, then “that person is virtuous” could be held to be true in the same way: there is indeed a virtuous person in front of you. This would, on a naively reasonable take, put virtuousness on a par with blackness; but while one is easily cashed out in terms of low-grade, mind-independent physics, the other is all bundled up with arguably less objective mind-dependent concepts. That’s why I am a moral anti-realist.

What Kind of Realist Are You?

Chat us up in the comments!