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Euclid of Alexandria revolutionized the way that mathematics is written, presented or thought about, and introduced the concept of mathematical proofs. Discover what it takes to move from a loose theory or idea to a universally convincing proof.

Lesson by Scott Kennedy, animation by Karrot Animation.

[Via IHC]

A bit of fluff that very much misses the point.

In Maths, you start with a small set of assumptions. Eveything else is derived from those assumptions, one bit at a time, in a manner that ensures that if the assumptions are true then that bit will also be true. And hence everything in Maths is true. Not just theory, but true. There are very few other disciplines where you can say that.