If interested in just 1 let me know. I've always been a space travel guy and then I read A City On Mars by Kelly and Zach Weinersmith, and it made a convincing case against the idea that we could ever even do as much as a small moon city where we'd have to pay for air like in the Heinlein books. And I read some other stuff that pointed out that the level of resources we'd have to commit to build a space colony would essentially strip the world of everything we need to survive, so that was a downer too. I'm an optimist though, but I'm the sort who says "well scientific breakthroughs change everything," but to do that we need someone to truly think of something new, not just incremental changes like reusable rockets. (Clears throat, flips off Elon). We won't get to space using ideas from the worst people on Earth. The rich are not creative. They're rich because they know how to sell, not to create. They want to make money not progress. We need people who actually want progress.