Nature is a hanging judge," goes an old saying. Many tragedies come from our physical and cognitive makeup. Our bodies are extraordinarily improbable arrangements of matter, with many ways for things to go wrong and only a few ways for things to go right. We are certain to die, and smart enough to know it. Our minds are adapted to a world that no longer exists, prone to misunderstandings correctable only by arduous education, and condemned to perplexity about the deepest questions we can ascertain.

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

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

But the newest research is showing that many properties of the brain are genetically organized, and don't depend on information coming in from the senses.

The doctrine of the sacredness of the soul sounds vaguely uplifting, but in fact is highly malignant. It discounts life on earth as just a temporary phase that people pass through, indeed, an infinitesimal fraction of their existence…the gradual replacement of lives for souls as the locus of moral value was helped along by the ascendency of skepticism and reason

Just as blueprints don't necessarily specify blue buildings, selfish genes don't necessarily specify selfish organisms. As we shall see, sometimes the most selfish thing a gene can do is build a selfless brain. Genes are a play within a play, not the interior monologue of the players.

Solving a problem in a hundred years is, practically speaking, the same as not solving it at all.