''The world will not grow and proper without population growth. That means eventually expanding civilisation to other planets. The Universe is a big place. There's plenty of room for say trillions of trillion of people, at least.''
We can't leave here until we learn to live in harmony with each other and the rest of the planet. Do you really want to inflict this peutrid mess on other planets? Don't bother answering that, you don't see what's under your nose.
