“People do more for their fellows than return favors and punish cheaters. They often perform generous acts without the slightest hope for payback ranging from leaving a tip in a restaurant they will never visit again to throwing themselves on a live grenade to save their brothers in arms. [Robert] Trivers together with the economists Robert Frank and Jack Hirshleifer has pointed out that pure magnanimity can evolve in an environment of people seeking to discriminate fair weather friends from loyal allies. Signs of heartfelt loyalty and generosity serve as guarantors of one s promises reducing a partner s worry that you will default on them. The best way to convince a skeptic that you are trustworthy and generous is to be trustworthy and generous.”

“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.”

“Evolutionarily speaking, there is seldom any mystery in why we seek the goals we seek — why, for example, people would rather make love with an attractive partner than get a slap on the belly with a wet fish.”

“Challenge a person's beliefs, and you challenge his dignity, standing, and power. And when those beliefs are based on nothing but faith, they are chronically fragile. No one gets upset about the belief that rocks fall down as opposed to up, because all sane people can see it with their own eyes. Not so for the belief that babies are born with original sin or that God exists in three persons or that Ali is the second-most divinely inspired man after Muhammad. When people organize their lives around these beliefs, and then learn of other people who seem to be doing just fine without them--or worse, who credibly rebut them--they are in danger of looking like fools. Since one cannot defend a belief based on faith by persuading skeptics it is true, the faithful are apt to react to unbelief with rage, and may try to eliminate that affront to everything that makes their lives meaningful.”

“The indispensability of reason does not imply that individual people are always rational or are unswayed by passion and illusion. It only means that people are capable of reason, and that a community of people who choose to perfect this faculty and to exercise it openly and fairly can collectively reason their way to sounder conclusions in the long run. As Lincoln observed, you can fool all of the people some of the time, and you can fool some of the people all of the time, but you can't fool all of the people all of the time.”

“I find a naturalistic understanding of human nature to be indispensable to leading a wise and mature life, and it is often exhilarating. Wisdom consists in appreciating the preciousness and finiteness of our own existence, and therefore not squandering it; of being cognizant of what makes people everywhere tick, and therefore enhancing happiness and minimizing suffering; of being alert to limitations and flaws in our own judgments and decisions and passions, and thereby doing our best to circumvent them. The exhilaration comes from understanding that we are a part of natural world; that deep mysteries can be explained; and that the world -- including our own mental lives -- can be intelligible, rather than a source of superstition and ignorance. Yes, mortality sucks, but given that it exists, I'd rather know that than be kept in a childlike state of delusion.”

“The more you think about and interact with other people, the more you realize that it is untenable to privilege your interests over theirs, at least not if you want them to listen to you. You can’t say that my interests are special compared to yours any more than you can say that the particular spot that I am standing on is a unique part of the universe because I happen to be standing on it that very minute.”