Uncle John knows pretty much everything—and if he doesn’t, he heads his massive research library, or puts one of his many associates on the case. So go ahead: In the comments below, ask Uncle John anything. (And if we answer your question sometime, we’ll send you a free book!)
“It’s not rocket science” is a droll, vaguely insulting phrase people say to somebody struggling to solve a problem, or work their way out of a difficult situation. It means “it’s not that hard,” bringing up a mock parallel with rocket science, which, by all reasonable measures, is probably pretty hard. (Sending a rocket into space involves math, chemistry, mechanical engineering–ugh, our brains hurt.)
The phrase entered the lexicon in the 1940s. That was about when rocket science, or the world of aerospace, began in earnest. The group of German scientists responsible for making the advanced V-2 rockets that were used by the Nazis to bomb London, including among them Werner Von Braun, were captured by Allied troops. They were drafted into switching sides, and with Albert Einstein already working for the U.S., the nascent world of rockets kicked into high and public gear. It was especially true after the end of World War II, when rocket science could be used to focus on peaceful means, such as space exploration, rather than weaponry. By the year 1950, “rocket science,” science-fiction only a decade earlier, was very real but still so exotic that it was synonymous with “incredibly difficult.” It was a common slang term, but print references didn’t appear until the 1980s.
Before these brave new frontiers of science were crossed, however, how were people dismissive of others trying to do something hard? They used phrases like “as easy as pie” or “as easy as falling off a log.”