When I was a student in history classes, a common mantra was: Don't judge past people by present standards; that's anachronistic.

One of the shifts happening now is the opening up of that question. I'm curious how a new wave of history teachers are teaching their students.

Personally, I welcome this opening up of the question. It always seemed a little strange to me that the ancient Greek philosophers' embrace of slavery was just kept to the side, while we savored their every word about democracy and the good life.

It's very complicated. Is every man who opposed women's suffrage before the twentieth century morally canceled? Because that would be close to every man, probably.

Or how do we assess a figure like Grant, who did the wrong thing and also did a very, very right thing?

The debates on statues and flags that we're having right now is, I think, a proxy war for a re-thinking of how history itself should be taught.

We are pushing toward a revival of anachronism, in a way, but selectively. On some things, we will judge people by present mores.

On other things, we will keep judging people by the standards of their time. I'm interested in how this will be worked out. What offenses of present mores become unforgivable, even though "everyone was doing it," and what is excused?

Someone write (or suggest) a book on this!

With the statues, slavery may be an easy case. The kind of thing you can say people should have known to be wrong in any era. Because people around them were arguing so.

But what about people who fought to defend feudalism, or patriarchy, or monarchy? How far do we go?

I know this is Twitter, but I have no answers here. Just lots of questions.

What do you think?