I’ve long struggled to understand how Thomas Jefferson could declare all men are created equal, how he could condemn slavery as a slaveowner himself, and simultaneously have a relationship with at least one of his slaves. The contradictions between conviction and behavior seems impossibly hypocritical and alien for an otherwise brilliant man.

But we ourselves do something very similar. Most of us have eaten meat our entire lives. We don’t dwell too much on the idea that the animals we kill, clean, cook and eat are herd animals with some social and emotional sense – they know who among them is aggressive, who is cooperative, who leads. They recognize external threats, feel fear and contentment. Their temperaments vary; they have personalities.

We grew up on a culture that normalized eating cows, chickens, fish and more. That’s not a judgment, merely an observation. We grew up thinking of it as normal. (Unless, of course, you have vegetarian parents!)

Jefferson grew up the same way with respect to slavery. It was a given. It was the way the world worked if you had a farm in the South. His entire generation grew up in that world. It wasn’t a world they created, and at the time it didn’t seem possible to create a world without it, because so much of the early U.S. was economically dependent on slavery. It took a war, hundreds of thousands of lives, and several generations for change to come.

Slavery was always wrong, but we see it much more clearly in hindsight. Yes, there were people who saw it clearly at the time, too…just as we have vegetarians among us today.

Circumstances change, but large-scale social patterns persist.