Sex and excretion are reminders that anyone's claim to round-the-clock dignity is tenuous. The so-called rational animal has a desperate drive to pair up and moan and writhe.

Obviously no language is innate. Take any kid from any race, bring them up in any culture and they will learn the language equally quickly. So no particular language is in the genes. But what might be in the genes is the ability to acquire language.

Trivers, pursuing his theory of the emotions to its logical conclusion, notes that in a world of walking lie detectors the best strategy is to believe your own lies. You can’t leak your hidden intentions if you don’t think they are your intentions. According to his theory of self-deception, the conscious mind sometimes hides the truth from itself the better to hide it from others. But the truth is useful, so it should be registered somewhere in the mind, walled off from the parts that interact with other people.

Anything that makes it easier to imagine trading places with someone else increases your moral consideration for that other person.

Violent movements attract thugs and firebrands who enjoy the mayhem. Violent tactics provide a pretext for retaliation by the enemy and alienate third parties who might otherwise support the movement.

Consistent style prevents presentation from getting in the way of content.

Heritability pertains to the entirety of the genome, not to a single gene.