Time travel, by its very nature, was invented in all periods of history simultaneously.
Douglas AdamsThe Answer to the Great Question... Of Life, the Universe and Everything... Is... Forty-two,' said Deep Thought, with infinite majesty and calm.
Douglas AdamsThere was one planet off in the seventh dimension that got used as a ball in a game of intergalactic bar billiards. Got potted straight into a black hole.
Douglas AdamsAfter a while he played with the pencil and the paper again and was delighted when he discovered how to make a mark with the one on the other. Various noises continued outside, but he didn't know whether they were real or not. He then talked to his table for a week to see how it would react.
Douglas Adams