But the 20th century suffered "two" ideologies that led to genocides. The other one, Marxism, had no use for race, didn't believe in genes and denied that human nature was a meaningful concept. Clearly, it's not an emphasis on genes or evolution that is dangerous. It's the desire to remake humanity by coercive means (eugenics or social engineering) and the belief that humanity advances through a struggle in which superior groups (race or classes) triumph over inferior ones.

Being smarter gives you a tailwind throughout life. People who are more intelligent earn more, live longer, get divorced less, are less likely to get addicted to alcohol and tobacco, and their children live longer.

In many Muslim countries, witchcraft is not only on the books as a crime, but is commonly prosecuted. In 2009, for example, Saudi Arabia convicted a man for carrying a phone booklet with characters in an alphabet from his native Eritrea, which the police interpreted as occult symbols. He was lashed three hundred times and imprisoned for more than three years.

As every student in Philosophy 101 learns, nothing can force me to believe that anyone except me is conscious. This power to deny that other people have feelings is not just an academic exercise but an all-too-common vice, as we see in the long history of human cruelty.

Language is a window into human nature, but it is also a fistula, an open wound through which we're exposed to an infectious world.

I do look for openings where I can overturn popular misconceptions, but unlike Christopher Hitchens, I am neither a contrarian nor a lone heretic. I like to have a significant number of academics watching my back.

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.