But eventually, as we get into the second and first century BCEs, it goes under Roman control. And we've talked about this classical period, all of the various contributions. We've talked about the contributions in philosophy from people like Socrates, and Socrates' student Plato, and Plato's student Aristotle. But there are also significant contributions in mathematics. You have Pythagoras, who actually predates these philosophers, and he's most famous, especially to many of us, for his Pythagorean theorem and a lot of mathematics and the foundations of a lot of geometry. But he and his followers, they were actually creating something of a mysticism, of a religion around mathematics, and even a philosophy that would later influence some of the other philosophers that we talk about, especially this ideal of ideal platonic forms. You can imagine, if you're studying perfect right triangles, there's no such thing as a perfect right triangle in the universe.