 you start seeing that the Earth is being terraformed again by humans slowly coming out of the bunkers. And if you go out 400 years, you see it's sort of a Garden of Eden. The humans are much wiser, much smarter, much more careful about their environment, and very carefully putting greenhouses all over the place in the sense of re-terraforming and bursting the whole planet into life. I have not gone out further than 400 years. Robert Monroe at the Monroe Institute, when he was still alive, he and some others had gone out as far as 1,000 years.