The Noah rule: Predicting rain doesn't count; building arks does.

When we build our own colonies, we can do them in near-Earth vicinity, because people are going to want to come back to Earth. Very few people - for a long time, anyway - are going to want to abandon Earth altogether.

Forethought we may have, undoubtedly, but not foresight.

A bird is like an instrument working according to mathematical law, and it is in the capacity of man to reproduce such an instrument.

Men standing in opposite hemispheres will converse and deride each other and embrace each other, and understand each other's language.

It's very clear that AI is going to change literally every job. Maybe there's a job in the world that AI won't change, but I haven't thought of it.