"But let us never forget, either, as all conventional history of philosophy conspires to make us forget, what the 'great thinkers' really are: proper objects, indeed, of pity, but even more, of horror."
David Stove's "What Is Wrong With Our Thoughts" is a critique of philosophy that I can only call epic.
The astute reader will of course find themselves objecting to Stove's notion that we should be catologuing every possible way to do philosophy wrong. It's not like there's some originally pure mode of thought, being tainted by only a small library of poisons. It's just that there are exponentially more possible crazy thoughts than sane thoughts, c.f. entropy.
But Stove's list of 39 different classic crazinesses applied to the number three is absolute pure epic gold. (Scroll down about halfway through if you want to jump there directly.)
I especially like #8: "There is an integer between two and four, but it is not three, and its true name and nature are not to be revealed."
The trouble there is the claim of a rational mind, in my opinion. It's not logically necessary that our evolved brains, hacked by culture, are going to mirror reality in their most basic perceptions and intuitions.
The space of all possible minds includes some which have a notion of number and counting and an intuitive mental arithmetic, but for which 2 and 2 really do seem to make 3 when they think of it. These minds, of course, would notice empirical contradictions everywhere: they would put two objects together with two more, count them, and count four instead of three, when it's obvious by visualizing in their heads that two and two make three instead. Eventually, a sufficiently reflective mind of this type would entertain the possibility that maybe two and two do actually make four, and that its system of visualization and mental arithmetic are in fact wrong, as obvious as they seem from the inside. Switching "three" and "four" in this paragraph just illustrates how difficult accepting that hypothesis might actually be for such a mind.
The thing is, we ourselves are in this situation, not with arithmetic (fortunately, we receive constant empirical reinforcement that 2+2=4 and that our mental faculties for arithmetic work properly) but with our biases of thought. Things like our preferences and valuations seem to be rational and coherent, in that we can usually defend them all with arguments that look solid and persuasive to us. But occasionally this fiction becomes untenable, as when we are shown to have circular preferences in situations of risk and reward. As Eliezer put it in Zut Allais:
Or, in this case, "Don't start by assuming that our minds work rationally whenever they see something as obvious! If this is true, it is an empirical fact; and you should be able to see the alternative as possible!"
Indeed, 2+2=4 is only true in some contexts. For example, sometimes 1+1=1 -- in contexts where separate objects lose their distinct identity as soon as they are grouped. (Think of a particular object several times. How many times did you think of it? But how many objects did you think of?)
Later edit: It is interesting that such a benign comment would get 4 down votes. Perhaps I understand this group well enough to guess why: the experiment I suggested is ... (read more)