Does the Great Man approach to history still have use?

[Belacqua]

The more I think about it, the more obvious it becomes to me that history is hugely affected by the choices and deeds of peculiar people who just happen to have the right brains and the right lives and be born at the right time.

The problem seems like a false dichotomy to me. It's not either/or.

So let's say there are changes in society that have been a long time coming. Economically, politically, the situation is ripe. If Napoleon doesn't come along to institute these changes, then somebody else will. 

But economic and political trends don't enact themselves. Human beings must enact them. Social changes don't come about unless people make the changes. 

So maybe Napoleon was only carrying out the inevitable changes that had been building for a long time. Still, it was he who did it. All the contingencies came together in one individual. 

I think your example is good. Math had advanced to the point where somebody could invent calculus. But that advancement had to manifest itself in the mind of one or two very amazing people. 

And of course it seems inevitable to us after it happens. But we have no way of knowing what other changes might have occurred if some individual had had the right combination of qualities to make them happen. Societal trends are always in flux, and the contingent ways in which they get enacted make a big difference. 

The German economy needed big changes, and antisemitism had been rampant in Germany for years. But if you could go back and kill baby Hitler, those two things might not have combined in quite the way they did.