My opinions about human nature are shared by many psychologists, linguists, and biologists, not to mention philosophers and scholars going back centuries.

... people notice differences and expect every difference in form to convey some difference in meaning.

An eye for beauty locks onto faces that show signs of health and fertility - just as one would predict if it had evolved to help the beholder find the fittest mate.

I try to jog in every city I visit, and I particularly enjoy harbour-front paths that let me ogle big ships, railroad bridges and the ruins of factories and warehouses.

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.

You could think of an ecosystem as a bunch of antagonistic arms races, almost: Everything that an animal depends upon for food is the body part of some other animal or plant who would just as soon keep that body part for itself.

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.