Toolkits for the MindProgramming languages shape the way their users think—which helps explain how tech startups work and why they are able to reinvent themselves. When the Japanese computer scientist Yukihiro Matsumoto decided to create Ruby, a programming language that has helped build Twitter, Hulu, and much of the modern Web, he was chasing an idea from a 1966 science fiction novel called Babel-17 by Samuel R. Del
