Imagine that you’re 80 years old, looking back on your life and all the things you have accomplished. What would you like to see? Perhaps you’d like to see that you had a happy life, a family and success in some line of work.

But I suspect you’d also like to see that you had made a positive impact in some way: that somehow others benefited from your existence. After all, when we step back to consider the question, what beauty is there in a life lived only in pursuit of one’s selfish ends? Presumably, then, this has implications for now: presumably we’d like to make a positive impact while we still can.

Nowadays, we’re especially worried about risks—about the risk of getting COVID if we hop on a plane or go to an in-person class, or about the risk of dying if we get COVID. And some risks are worth taking, but others aren't; it depends partly on how we estimate the risks.

So, then, how good are we at estimating risk? And how should we estimate risks?