A simple problem

Sometime in your life, you have almost certainly had a dream so realistic that you didn’t recognize it as a dream. You didn’t know that you had been asleep until you woke up. Perhaps you were sad to awaken; maybe you had been flying. Perhaps you were happy to awaken; you may have been having a nightmare. For some period, though, appearance and reality differed. You appeared (to yourself) to be doing something else, but you were really asleep in your bed.

Of course, there are many times when appearance and reality diverge. The split may be caused by drugs, or fever, or mental illness, or any number of other things, some of which are quite banal, things like optical illusions. Often we can tell somehow that things are not appearing as they should be. We are aware that something has gone wrong in our heads. Other times, though, it is impossible to tell. Occasionally, as in the case of some kinds of mental illness, the ‘break from reality’ can last a very, very long time—so long that we lose touch entirely.

Let me, then, ask you a simple question: how do you know that you are not dreaming, hallucinating, or are otherwise out of touch right this very minute? Maybe you are only imagining this book in your hand. Maybe you are, in fact, going kooky. Maybe it has been happening for such a long time that you have forgotten.

How do you know that what you see is a faithful representation of reality?

This question is a philosophical question. You can tell it is a philosophical question because it has several characteristics of the kind. It is:

• Simple
• Irritating
• Meant to be answered (and perhaps can only be answered) with argumentation. Science is of no use.

Finally, and importantly, you—you sitting right there—you will never, ever, answer this question correctly. No offense: nobody ever answers philosophical questions correctly, not even the greatest philosophers. In the 2500 years that people have been doing philosophy, not one question has been answered correctly. Not a single one.

What is philosophy?

Some people say that philosophy is the ‘love of wisdom’. Others say that it is the father of the sciences, or the world’s greatest waste of tuition. I say that philosophy is giving bad answers to good questions.

There have been many bad answers to the simple question I asked above. Some easy ones are pinching yourself, calling Heidi Klum (or Ryan Phillipe), trying to fly, and just waiting to wake up. All of these answers have problems, though. It’s not hard to imagine a dream (or a hallucination) so real that you felt pain, or couldn’t get Ms Klum to come over, or couldn’t fly. You can at least conceive of a dream so real that this kind of thing happens. You can certainly imagine a hallucination like this. That means, if you are really being strict, that you do not know for sure that you are not asleep or hallucinating right now. While it may be unlikely, you can’t be absolutely certain.

Several years ago, the movie The Matrix considered just this problem. In it, Neo discovers that his body is in a post-apocalyptic, machine-ruled, lightless world, while his mind is in a computer program simulating twentieth-century America. In other words, Neo comes to know that he has been, in essence, hallucinating. He had broken from reality. While everyone else in the matrix is ignorant of the real ‘reality’, Neo somehow knows that things aren’t what they appear.

So, here is a new question, more suitable for our times: how do you know that you are not living in the matrix? The matrix is a totally immersive hallucination. How can anyone tell when they are being completely fooled?
There are actually two questions implicit in the above problem of the matrix.

1. What is reality?
2. How do you know it?

The first is the fundamental question of metaphysics: what is real? The second is the fundamental question of epistemology: how do you know what you know? These may seem like strange questions. They are clearly philosophical questions: they are simple, bothersome, and hard to answer clearly.

Metaphysics

Metaphysics seems like a dumb thing to study. Reality seems, well, quite real; it is all too pressing for many of us. Accordingly, it appears quite foolish to ask what reality is—it’s this stuff right here.

Nearly all scientists presently think that the universe is composed of matter and space. Yet in the past, philosophers and scientists (they have been one and the same) thought otherwise. They hypothesized that the universe contained matter, void, energy, minds, Forms, essences, monads, or a myriad of other, strange things.

Clearly, scientists have now cornered most of the metaphysical market, but there are still unresolved questions. Take, for instance, numbers. What are they? What do two cups, two ducks, and two bikes have in common? ‘Two-ness’, it seems—but that doesn’t really answer the question. What is two-ness?

This is certainly a strange question, and it is worthy of a little attention. Mathematics seems to rule the universe; nothing happens that cannot be described through mathematics. The movements of both the smallest particles and the largest planets are described in the same mathematical language. In some serious way, though, we have no idea what this language means.
Despite the importance of numbers, very few people have ever stopped to wonder just what numbers are. Are they real? What does it mean to say that they are real? Since they seem to govern the material world, are they somehow more real than it? Perhaps they are merely a language that we use to describe the material world. All of these are serious, plausible, ideas.
There are other metaphysical questions. Among them are:

• What is a law of nature?
• What is existence?
• What is causality?
• What is time?
• What are kinds or categories?

Nobody has come up with a final answer for any of these. Trying to answer these questions, though, is both fun and revealing. If you feel so inclined, ask yourself this: what makes the matrix less real than the machine-ruled, lightless world that Neo found himself in? We feel it is less real—but why?

Epistemology

Epistemology is another area of philosophy. It asks how we know what we know.

My students tend to be deferential. They say that teachers taught them what they know. That’s goofy. Teachers taught me only some of what I know. Other things, though, I learned by myself.

Look at this thing, for instance: O

It’s a circle, right? How do you know? There is, as you’ve probably heard, no such thing as a perfect circle. This one is no exception. That dot only resembles a circle. It has small imperfections.

If you’ve only ever seen things that resemble circles, how do you know what a circle is? Do you somehow mentally remove the imperfections in any particular circle? If so, how did you get the idea of perfection? To get it, did you mentally remove the imperfections from perfect things? That doesn’t make sense, so where did it come from?

One possibility is that you abstracted from several circles on paper to a kind of circle-ness. I think that this is often what my students mean when they say they have been taught. Someone showed them some circles, and said, “Look! These are circles! Get it? Take what they have in common, and that’s a circle.” But in order to see what any circles have in common, we need to have some idea of what to look for. Why would we take the roundness as common, and not the blackness? Why take the roundness and not the line-ness?

Perhaps you were born with the idea of a circle. As far as I know, every culture knows what a circle is. Maybe there are some ideas we are all born with, ideas like up, down, triangularity, circularity, and time. Maybe. But that also sounds a bit fishy: why do we also teach these ideas in school if we were born with them?

There are other difficult epistemological questions. Here are a few:

• What is truth? What is falsity?
• What is justification?
• What is evidence?
• What is a belief?
• How should (or do) we make generalizations?

The Matrix included quite a bit of epistemology. Neo started by trying to discover the truth about the matrix and reality. Eventually, he discovered that he had been living in a virtual world. Had Neo been slightly more clever, though, he would have continued questioning. Maybe the grungy ship and torn sweaters were also just a dream! Neo was very stupid to assume that the grungy world was the real one: given his experience, he should have realized that it’s very hard to tell what is real and what is imaginary.

If Neo had only studied a little philosophy, he would have questioned his own epistemology. He would have wondered how he could be sure that he really knew what he thought he knew.

Finally, some real philosophy

Interestingly, the Wachowski brothers did not invent the problem of the matrix. They stole it, probably from Hilary Putnam, a famous philosopher of the twentieth century.
Putnam is a remarkable fellow—and he is the only living philosopher that I will mention in this whole book. Putnam is remarkable both for his brilliance and for his remarkable criticisms of himself. While most philosophers seem to never change their opinions once they graduate, Putnam has changed his mind many times and has often criticized his former viewpoints. I think that this speaks very highly of him.

One of Putnam’s rather famous ideas is of the brain in the vat. It’s not entirely original, as we’ll see, but it is concise. Compare what Putnam said to what the Wachowski brothers shot.

The case of the brain in a vat, by Hilary Putnam

Here is a science fiction possibility discussed by philosophers: imagine that a human being (you can imagine this to be yourself) has been subjected to an operation by an evil scientist. The person’s brain (your brain) has been removed from the body and placed in a vat of nutrients which keeps the brain alive. The nerve endings have been connected to a super-scientific computer which causes the person whose brain it is to have the illusion that everything is perfectly normal. There seem to be people, objects, the sky, etc.; but really, all the person (you) is experiencing is the result of electronic impulses travelling from the computer to the nerve endings. The computer is so clever that if the person tries to raise his hand, the feedback from the computer will cause him to ‘see’ and ‘feel’ the hand being raised. Moreover, by varying the program, the evil scientist can cause the victim to ‘experience’ (or hallucinate) any situation or environment the evil scientist wishes. He can also obliterate the memory of the brain operation, so that the victim will seem to himself to have always been in this environment. It can even seem to the victim that he is sitting and reading these very words about the amusing but quite absurd supposition that there is an evil scientist who removes people’s brains from their bodies and places them in a vat of nutrients which keep the brains alive. The nerve endings are supposed to be connected to a super-scientific computer which causes the person whose brain it is to have the illusion that…

When this sort of possibility is mentioned in a lecture on the Theory of Knowledge, the purpose, of course, is to raise the classical problem of scepticism with respect to the external world in a modern way. (How do you know you aren’t in this predicament?) But this predicament is also a useful device for raising issues about the mind/world relationship.
Instead of having just one brain in a vat, we could imagine that all human beings (perhaps all sentient beings) are brains in a vat (or nervous systems in a vat in case some beings with just a minimal nervous system already count as ‘sentient’). Of course, the evil scientist would have to be outside—or would he? Perhaps there is no evil scientist, perhaps (though this is absurd) the universe just happens to consist of automatic machinery tending a vat full of brains and nervous systems.
This time let us suppose that the automatic machinery is programmed to give us all a collective hallucination, rather than a number of separate unrelated hallucinations. Thus, when I seem to myself to be talking to you, you seem to yourself to be hearing my words. Of course, it is not the case that my words actually reach your ears—for you don’t have (real) ears, nor do I have a real mouth and tongue. Rather, when I produce my words, what happens is that the efferent impulses travel from my brain to the computer, which both causes me to ‘hear’ my own voice uttering those words and ‘feel’ my tongue moving, etc., and causes you to ‘hear’ my words, ‘see’ me speaking, etc. In this case, we are, in a sense, actually in communication. I am not mistaken about your real existence (only about the existence of your body and the ‘external world’, apart from brains). From a certain point of view, it doesn’t even matter that ‘the whole world’ is a collective hallucination; for you do, after all, really hear my words when I speak to you, even if the mechanism isn’t what we suppose it to be. (Of course, if we were two lovers making love, rather than just two people carrying on a conversation, then the suggestion that it was just two brains in a vat might be disturbing.)
I want now to ask a question which will seem very silly and obvious (at least to some people, including some very sophisticated philosophers), but which will take us to real philosophical depths rather quickly. Suppose this whole story were actually true. Could we, if we were brains in a vat in this way, say or think that we were?

Our first reading, from René Descartes’ Meditations takes up this classical problem of epistemology. Descartes asks how we know what we know and if there is anything that we can know for certain. He comes up with an amazing answer.

Another simple philosophical problem

Forgive me for the lie in this chapter’s title. I’m not going to use a single problem. Philosophy is complicated, and it actually takes two philosophical problems to convey all of it. Sorry.
This time, imagine that you are in a lifeboat, with a juicy fat boy, an old skinny man, and a pregnant woman. You have no food, and if you do not eat today, all four of you will die.
What do you do?

More importantly, how do you decide what to do?

Clearly, these are philosophical questions. (They are simple, irritating, and meant to be answered with argumentation.) They have another characteristic of the genre too: they are quite ridiculous and somewhat disgusting.

Of course, the answers to the first question are facile. The second question is much more difficult. Perhaps we should eat according to who would feed us for the longest time. The pregnant woman, then, would be a good choice. Perhaps, though, we should respect her because she is bringing more life into the world. She might get an exemption that a merely fat woman would not. The juicy fat boy is the second best solution. But he is young. Perhaps we should try to determine who will contribute most to the world and eat those who are past their prime. While he is skinny and tough, the old man is clearly the least useful. Or, and this is a choice my students very rarely consider, perhaps one ought to sacrifice oneself for the goodness of the group. Finally, maybe nobody should eat; it might be better to die than to be so debased.

All of the criteria are plausible:

• Eat the most calories per life sacrificed,
• Give those who have most to live the chance to go on
• Sacrifice for the greater good
• Die rather than do evil

All of these criteria are ethical rules. They are rules to govern our lives. (Except for the first one. It is not much of a rule, at all.)

This is the third area of philosophy: ethics. While ethics is the study of what is right and wrong, that soon gets boring. It is much more interesting to try to find rules we can use to decide what is right or wrong. These rules fun to debate, and philosophers spend a lot of time considering them. Eating the fat boy—that’s boring. Deciding how to decide who to eat is much more exciting.