I'm going to read you something that he wrote.

I'm going to try to tell you today why the events in the 20th century happen.

So, the map that I wrote was a part of,

and I'm going to try to tell you something that I wrote.

I'm going to try to tell you today why the events in the 20th century

happen, so the mass genocidal movements in particular,

which were probably the defining characteristic of the 20th century.

And then also what that has to do with individual psychology.

My first degree was in political science, and I was interested in political science

because I was interested fundamentally in the reason that human societies went to war.

And when I was studying political science, which is quite a long time ago,

the fundamental theory that underlie political scientists' explanations for conflict

were economic.

People fight over resources, and that never seemed reasonable to me because,

first of all, obviously, many wars are fought for other reasons than resources.

Two Central American countries, I think it was Guatemala and the Honduras,

if I remember correctly, went to war over a soccer game.

So the outcome of a disputed outcome of a soccer game.

And even if you do think that the reason that groups of people engage in conflict

are for economic reasons, that doesn't exactly explain much because

that doesn't explain whether they're fighting for,

because of absolute differences in wealth, or because of relative discrepancies in wealth,

...