Everyone’s heard of Aristotle. Democritus? Not so much. And that’s a major kick in the teeth for the pre-Socratic philosopher, because it was Democritus who came up with the atomic theory of the universe way back in 430 BCE. He believed that all material bodies must be made up of some invisibly small “atoms” - but unfortunately, Aristotle rejected the idea, calling it “ridiculous”.

That’s right - we could have had major scientific developments much earlier, but everyone believed Aristotle over Democritus until around 1800, when English scientist John Dalton revived the idea. Still, Democritus had the last laugh - not because of any achievement, just that he was literally known as the ‘laughing philosopher’ because of his emphasis on the value of cheerfulness.