Suppose I told you that I knew for a fact that the following statements were true:
- If you paint yourself a certain exact color between blue and green, it will reverse the force of gravity on you and cause you to fall upward.
- In the future, the sky will be filled by billions of floating black spheres. Each sphere will be larger than all the zeppelins that have ever existed put together. If you offer a sphere money, it will lower a male prostitute out of the sky on a bungee cord.
- Your grandchildren will think it is not just foolish, but evil, to put thieves in jail instead of spanking them.
You’d think I was crazy, right?
Now suppose it were the year 1901, and you had to choose between believing those statements I have just offered, and believing statements like the following:
- There is an absolute speed limit on how fast two objects can seem to be traveling relative to each other, which is exactly 670,616,629.2 miles per hour. If you hop on board a train going almost this fast and fire a gun out the window, the fundamental units of length change around, so it looks to you like the bullet is speeding ahead of you, but other people see something different. Oh, and time changes around too.
- In the future, there will be a superconnected global network of billions of adding machines, each one of which has more power than all pre-1901 adding machines put together. One of the primary uses of this network will be to transport moving pictures of lesbian sex by pretending they are made out of numbers.
- Your grandchildren will think it is not just foolish, but evil, to say that someone should not be President of the United States because she is black.
Based on a comment of Robin Hanson’s: “I wonder if one could describe in enough detail a fictional story of an alternative reality, a reality that our ancestors could not distinguish from the truth, in order to make it very clear how surprising the truth turned out to be.”1
Nonsense.
If the only relevant pieces of information you had were the race of each man, and the average intelligence of each race, then of course it would be rational to estimate that the man from the 'smarter' race were the smarter of the two. But this is very far from the truth. In the Obama-Bush example, there is more than enough evidence on the public record to swamp any racially determined prior.
I think the principle of 'treating people as individuals' exists to combat a couple of things. One is the tendency to form stereotypes on flimsy or non-existent evidence, to over-estimate the generality and force of those stereotypes that are factually based, and to treat prejudice (i.e. group membership-based priors) as a substitute for even very easily-gathered and reliable evidence about the individual. The other is the direct emotional harm done to people by treating them as members of a group first, and individuals second (if at all). It is possible for this harm to outweigh the benefits of otherwise-rational discrimination.
Even then, assuming the difference between the averages is one standard deviation of either race's distribution and each race's distribution is Gaussian, there is only 76% probability that the smarter guy is the one from the smarter race, which hardly counts as “must” in my book.