1. Life is complicated, and so is history. The good is mixed in with the bad. Don’t let the latter blind you to the former.

George Washington was a slaveholder. He also was essential to creating the country that invented modern ideas of human rights and made equality a plausible aspiration for billions of humans.

2. Don’t take the present for granted. It didn’t just happen. People had to make it happen. If it’s not perfect, this simply means there’s work left for you to do.

Democracy has serious shortcomings. It’s inefficient and lends itself to demagoguery. But a democracy is hard to turn into a despotism, and it’s a better guarantee of freedom than the alternatives that have been tried. Its laws are often clunky but they have a legitimacy that comes from popular approval.

3. If something about the past appalls you, don’t be disdainful—be encouraged. It means we humans have made progress to where we’re enlightened enough for you to be appalled. You can bet we’re doing things our descendants will shudder at.

Child labor was the norm for millennia. Now we can afford to send kids to school, and laws banning child labor have been a way to make attendance more likely.

Bear-baiting and dog- and cock-fighting were common amusements in many countries as recently as the 19th and early 20th centuries. Their cruelty was much of their appeal. Now they’re illegal and widely considered immoral.