A simple philosophical problem

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.

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 wake; you may have been having a nightmare. For some period, though, appearance and reality differed. You appeared (to yourself) to be doing something other than drooling face down.

Of course, there are many times when appearance and reality diverge. Drugs, fever, mental illness, or any number of other things (some of which are quite banal, like optical illusions), may cause the split. Usually, we can somehow tell that things are not quite right. We know 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 good 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 good question is a philosophical question. You can tell so because 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 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.

There have been many bad answers to the simple question I asked above. Some easy ones are pinching yourself, calling Jessica Alba (or Ryan Gosling), trying to fly, and just waiting to wake up. All of these have problems, though. It’s not hard to imagine a dream (or a hallucination) so real that you felt pain, or one in which you couldn’t get Ms. Alba (or Mr. Gosling) to come over, or in which you couldn’t fly. You can at least conceive of a hallucination so real that this kind of thing happens. That means, if you are really being strict, that you do not know for sure that you are not asleep or hallucinating right now. 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 figures out that he has been, in essence, hallucinating. He had a break from reality. While everyone else in the matrix is ignorant of the real ‘reality’, Neo somehow knows.

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 she is 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, irritating, and hard to answer.


Metaphysics tries to answer a simple question: what is reality? I know that seems stupid. Reality seems quite real; it is all-too pressing for many of us. It seems pretty stupid to ask what it is—it’s this stuff right here.

Indulge me. Scientists now think that the universe is composed of matter and space. Yet in the past they thought otherwise. They thought that the universe contained matter, void, angels, demons, energy, minds, Forms, essences, monads, or a myriad of other daft things.

But here is the freaky part. They knew about our current ideas (the atomic theory has been around for thousands of years) so they preferred their explanation to ours. You should really wonder why you’re so sure you got it right when really smart people for thousands of years thought you were wrong.

I’ll concede, though, that scientists have now cornered most of the metaphysical market. Even so, there are still unresolved questions. Take, for instance, numbers. What are they? What do two days and two ducks have in common? Not a lot, apart from something we might call ‘two-ness’. But that doesn’t really answer the question. What is two-ness?

This is an amazingly great question, even if it seems strange at first. Mathematics is deep. Math rules the universe. Everything that happens can be described through equations. The smallest particles and the largest planets, the blood in your heart and the plasma of the sun; they are governed by one math that even kids can learn. If you stop and think about it, this should blow your mind. The language of numbers is in charge.

In some serious way, though, we have no idea what this language means.

Very few people have ever stopped to wonder just what numbers are. Are they real? What does it even 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.

Numbers, though, are not atoms, matter, or space. They’re not part of that normal, scientific view of the universe that we take for granted. What are they? That’s a metaphysical question.

There are other metaphysical questions. Among them:

  • 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? Answer that, and you’re doing metaphysics.


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. Many things I learned by myself.

Look at this thing, for instance:


It’s a circle, right? But how do you know that? There is, as you’ve probably heard, no such thing as a perfect circle. This one is no exception. That circular thing only resembles a circle.

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, you would have needed to know what the perfect circle looks like so that you could remove the imperfect parts. But I was asking how you came up with the idea of the perfect circle in the first place, so that would be a quite roundabout answer: you remove imperfect parts from circles you see using the perfect circle in your mind to come up with the perfect circle (that was already in your mind).

Maybe 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 circularity!” But to see what any circles have in common, we need to have some idea of what to look for. Why take the roundness and not the line-ness or the bumpiness or the blueness? And where did we get the idea of roundness from anyway? It’s the same problem as before: we need to know what we’re looking for to see what we are looking at.

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?

Maybe you define it with words first? Maybe circles are part of our built-in mental frameworks? Maybe, maybe, but you get the idea: every answer has problems. That’s why this is a philosophical question.

The problem of the perfect circle is only one epistemological question. There are others, which may be more interesting,

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


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. It will blow your mind.

Another philosophical problem

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.

  • Who do you eat?
  • More importantly, how do you decide who to eat?

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 ridiculous and a little disgusting.

Of course, the answers to the first question are unimportant (unless you’re the one being eaten). 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. But maybe 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. By the calorie criterion, the juicy fat boy is the second best solution. Still, he is young. We should maybe consider who would contribute most to the world and eat those who are past their prime. If that’s the case, while he is skinny and tough, the old man is clearly lunch. 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:

  • Maximize calories per life taken
  • Maximize happiness and minimize unhappiness
  • Value youth and promise
  • Sacrifice for the greater good
  • Die rather than do evil

These are ethical rules (though they’re not all good ones), and they lead us to the third area of philosophy: ethics.

Ethics studies right and wrong, but simple lists of good and bad things are boring. It is much more interesting to try to find rules we can use to decide what is right or wrong. These rules are 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.

In short, ethics asks another simple question: How do we know what’s right and wrong?

By now, you won’t be surprised to hear that this is a surprisingly difficult question to answer. Many answers seem good at first blush but lead to outrageous consequences. Other, more nuanced systems lead to contradictions.


There is one last area of philosophy. I was hoping you wouldn’t notice. It’s logic.

I love logic, but it’s ridiculously hard. It is a mongrel of math and computer programming, just as difficult, and half as well-paying. It is technical, demanding, and amazing. It’s also way too hard for me. But, for the sake of parallelism, I’ll tell you the question it answers, kind of:

  • How do we systematize rational thought?

The thing is, logic is much more besides this. Math governs the very unfolding of the universe, and logic governs math.  Logic might very well answer “What was in god’s mind?”