Abstract: Informally known as The Big Three, Arthur C. Clarke, Isaac Asimov, and Robert Heinlein were arguably the most famous science fiction writers of the latter half of the 20th century. Interestingly, they all knew each other, both professionally and personally; Clarke corresponded with the other two regularly for decades. He even had an informal agreement with Asimov, the Clarke-Asimov Treaty, that if asked, they agreed to say that Clarke was the better science fiction writer and Asimov the bette…