Archive for Philosophy


I just finished Neal Stephenson’s new book Anathem. I enjoyed it quite a bit. The book is based on a lot of the Western philosophical tradition, albeit under different names. He provides an SF explanation for Plato’s Theory of Forms, which I think anybody has to appreciate, loosely (very loosely) based on some of Gödel’s work. And he is getting better at actually writing endings to his novels.


Syntax vs. Semantics

Is consciousness a purely syntactic process or does it require semantics? That is another way of asking whether, if you take a snapshot of all the neurons in a human brain, and simulate it on a computer, the resulting program will be conscious. Computers are purely syntactic engines: they simply manipulate symbols. So if consciousness requires semantics, then a program running on a computer can not be conscious.

Of course, if you asked the program whether or not it was conscious, it would simulate the answer that the human would give, and would say that it was conscious. In fact, by definition, it would give all the answers that the human would give. So to argue that the program is not conscious requires believing in something very much like zombies–people who act perfectly normal but are not conscious. I think that the whole idea of zombies is incoherent, and it baffles me that some philosophers appear to take it seriously. Consciousness is not something extra that gets added on to our brains, and thus can be added to some brains but not others. Anything which acts exactly like a conscious human must be conscious.

So that would seem to settle the question. Actually, though, it doesn’t. I’ve assumed that it is possible to simulate a human on a computer. I can see two reasons that that might not be possible.

The first is that human intelligence may require quantum operations. If the human brain is a way of turning quantum effects into macroscopic effects, then it need not be possible to simulate those effects on any non-quantum computer. And while we don’t fully understand what a quantum computer is at this point, it is at least possible that it is not a purely syntactic engine. A quantum computer can, supposedly, come up with the answer to a problem without walking through all the intermediate steps. In that sense a quantum computer is not a purely syntactic engine. This is similar to the way that one can argue that the spaghetti sorter–in which you represent all the inputs as strands of spaghetti, tap them on the table, and easily pick out the largest one–is not a purely syntactic engine. The spaghetti sorter uses physics to jump immediately to the right answer. A quantum computer may do the same thing. Admittedly, arguing that this is what we want “semantics” to mean is going to be a bit of a slog. But I think it is fairly clear that it is not what we mean by “syntax”.

The second reason it may not be possible to simulate a human on a computer is that it may not be possible for human consciousness to exist separated from the world. The simulated human brain may simply be unresponsive. Arguably one could proceed the simulate the whole world around the human, or at least the perceptible part of it. But at some point I think it is reasonable to ask whether this is possible even in principle. Simulating all the neurons in a brain already sounds pretty darn hard, but one imagine simplifying to just the neurons and the neurotransmitters. Simulating the whole world sounds pretty darn hard. Can we possibly do it without requiring a computer which is as complicated as the world? And that implies, again, a quantum computer.

My bias is to believe that computers can be conscious, and to believe that the brain is purely a syntactic engine. I think that the brain dampens quantum effects rather than magnify them. But I have to admit that the alternate argument is coherent and may be the truth.


Raising Meat

I’m a vegetarian for moral reasons. Animals raised for meat in this country are in general treated horribly (I think every meat eater should have some familiarity with factory farming of animals, since I think one should understand the consequences of a lifestyle one chooses). One question I’m occasionally asked is: is it OK to eat animals that you raise yourself in humane conditions, or that you hunt?

Clearly humans evolved hunting and eating meat, so it is in some sense natural. Obviously many other animals hunt and eat meat, but that is not particularly relevant since those animals are incapable of making moral choices. So one part of the question is whether something which is natural from our evolutionary history is therefore moral. I’ve argued in the past that the basis of our morality is our evolutionary history. However, it doesn’t follow that everything from our evolutionary history is moral. We are able to pick and choose. Observation of hunter gatherer tribes in New Guinea and the Amazon suggests that our evolutionary history included living in small bands and regarding people from other bands as subhuman others. We no longer accept that as a moral view–morally speaking, we now believe that all people are created equal.

Another side of the question is whether it is OK to use animals for anything. Some people have argued that keeping pets is immoral because it is unnatural for the animals. My view on that is that domestication is a choice. Humans have domesticated themselves–that is the choice we made in choosing agricultural and city living. I think it is morally OK for other animals to make the same choice, for all that they do it unconsciously. Some animals can not be domesticated–zebras are a well-known example. Some animals thrive on it, such as dogs. I think that keeping pets is OK, and, extending that slightly, I think it is OK to keep animals and use their byproducts such as wool, eggs, milk, and honey. That said, the details do matter: there are factory farms for dairy cows that are nearly as bad as the ones for meat cows, and that is not OK.

Would it be OK to raise a domesticated animal and then eat it after it dies of old age? Yes, I think it would. The only objection I see would be a sort of fastidiousness, the reason that we do not eat dog meat in this country. There is nothing wrong with that fastidiousness, but I don’t think it is a moral requirement.

Would it be OK to kill and eat an animal if you would otherwise starve to death? Yes, I think it would. I do think that humans have a right to life which somewhat exceeds that of other animals. This is a very hypothetical situation, though, and not only would it never happen today, it would be rather unlikely even in the distant past. For example, it’s not OK to head out into the desert with a cow and then conclude that you must eat the cow because there is nothing else around: you acted wrongly in heading out to the desert with that plan in mind.

This brings us to the real question, which is whether it is OK to raise a domesticated animal under humane conditions, and then kill it and eat it. This is close to the line between the morally acceptable and the morally unacceptable. Which side of the line does it fall on? It’s possible to imagine an animal making an informed choice to accept a domesticated lifestyle in exchange for an early death. Douglas Adams, himself a vegetarian, put a humorous spin on this in The Restaurant at the End of the Universe. In the real world, in some species of mites the mother never lays her eggs; instead, the mother dies, the eggs hatch inside her body, and the babies eat their way out.

Since animals can’t make that informed choice, we must make it for them. What I see is that animals struggle for life even in extreme conditions. I don’t think humans would make such a choice, except perhaps when in the depths of despair, and at base we are animals too. I don’t think animals would make that choice either.

So my conclusion is that it is not OK to raise animals for the purpose of killing and eating them, even if you do so humanely. It is close to the line of what is OK, but it falls on the far side.

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When I was in grade school we were taught that monotheism was a historical advance, comparable to agriculture or other notable inventions. For example, we learned that Akenhaten was a significant figure because he was the first historical figure to advocate monotheism, although it was later repudiated by his successor Tutankhaten aka Tutankhamun aka King Tut. (Akenhaten lived about two centuries before the first historical evidence of Judaism; Freud suggested that Moses was actually a monotheistic priest during the reign of Akenhaten). Even in grade school this argument seemed vaguely suspect to me. The advantages of agriculture seem clear, the advantages of monotheism less so.

These days I do see monotheism as something of an advance. The earliest cultures we know of believed in gods who were much like people, albeit people who were both powerful and sometimes unpredictable. In some cases the gods were simply ancestors. I think this is a natural consequence of our tendency to attribute events to causes. When we want to understand the weather, our impulse is to give it a personality and motivations. It’s only a small step to think that there is a powerful person–a god–who controls the weather.

This then becomes an obstacle to actually understanding what is happening. If you already have an explanation for the weather, and your explanation inherently incorporates unpredictability, there is little purpose to looking for a deeper explanation. Since I do think that scientific thought is an advance in human culture, it follows that these early religions prevented advances.

Monotheism reduces the mass of gods to just one. This god still controls the weather, but now there is just one entity that you have to understand. It becomes possible to seriously think about god’s will and hope to reach some conclusions about it. As thinking progresses, the god becomes more abstract—created the whole world, pays attention to everything—and it becomes easier to think in terms of fixed laws rather than whims. It’s still a big step to get to science, but it’s more feasible, and monotheism may be a necessary stopping point.

I was reminded of this line of thought while reading about the Gospel of Judas. Today I don’t see how it’s possible to see Judas as anything but a patsy—hence his lyric from Jesus Christ Superstar “I only did what you wanted me to.” The Gospel of Judas doesn’t really present him that way, but it does suggest that Judas was himself a human sacrifice to Christ. This was, after all, a time when animal sacrifices to the gods were routine, though not a practice of the Christians. The Gospel of Judas was an alternate view of the Christ story, one that was suppressed by the early church as they coalesced on a single view of the religion. Ditching the Gospel of Judas was a good move, since it seems pretty complicated. Anyhow, reading about it reminded me that there is a lot of contingency in the religions that we have today. Monotheism may have been an advance in retrospect, but, unlike agriculture, it wasn’t an advance at the time. I don’t see any reason to think that things could not have gone otherwise.

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One of the drawbacks of our secular age is that it is less clear what we should strive for in our lives. In medieval Europe it seems as though life goals were pretty clear for most people: keep your nose clean, and you get to go to heaven after you die. Heaven is a good place, and the details are left undefined because they are sort of hard to imagine.

Most people want to lead a good life, but my guess is that these days most people don’t really believe in a literal heaven. Without a set of rules handed down from the priests, how do we know what a good life consists of? Based on what I see in bookstores, a lot of people—at least enough for a niche publishing market—are aiming for happiness. A good life is a happy life.

This does not imply an outbreak of hedonism and selfishness, as many people are made happy by altruism and quiet reflection. However, to me, it doesn’t seem like the right sort of goal. I don’t think I have the goals of a good life fully pinned down, and it’s not like I think one should strive to be unhappy, but happiness as a goal doesn’t seem right to me. It seems to me that happiness should be a result of a good life. We should aim to do the right thing; if we succeed, we can expect to be happy. Aiming for happiness seems to put it the wrong way around.

Happiness by itself just seems too disconnected, too prone to short-circuiting a deeper examination of the situation.

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