A lot of the fun of Pinker’s book is his attempt to deduce human psychology from the assumption that our minds are adaptations for transmitting our genes. His last chapters are devoted to this and they range very broadly; including, so help me, one on the meaning of life. Pinker would like to convince us that the predictions that the selfish-gene theory makes about how our minds must be organised are independently plausible. But this project doesn’t fare well. Prima facie, the picture of the mind, indeed of human nature in general, that psychological Darwinism suggest is preposterous; a sort of jumped up, down-market version of Original Sin.
Psychological Darwinism is a kind of conspiracy theory; that is, it explains behaviour by imputing an interest (viz in the proliferation of the genome) that the agent of the behaviour does not acknowledge. When literal conspiracies are alleged, duplicity is generally part of the charge: ‘He wasn’t making confetti; he was shredding the evidence. He did X in aid of Y, and then he lied about his motive.’ But in the kind of conspiracy theories psychologists like best, the motive is supposed to be inaccessible even to the agent, who is thus perfectly sincere in denying the imputation. In the extreme case, it’s hardly even the agent to whom the motive is attributed. Freudian explanations provide a familiar example: What seemed to be merely Jones’s slip of the tongue was the unconscious expression of a libidinous impulse. But not Jones’s libidinous impulse, really; one that his Id had on his behalf. Likewise, for the psychological Darwinist: what seemed to be your, after all, unsurprising interest in your child’s well-being turns out to be your genes’ conspiracy to propagate themselves. Not your conspiracy, notice, but theirs.
more here.