jr_metaphysicist

I'm a metaphysicist hobbyist if there is such a thing. I'm writing a book on the history and nature of human knowledge and it deals specifically with the evolution of Reason and Science, and of course modern theoretical physics and quantum theory.

So you have inspired me to get a copy of Euclid's Elements, thank you for that. But I still do not see what Descartes added to Euclid's spatial models of X and Y coordinates, and in turn as I understand it a third dimension Z. Was it simply the algebra that defined the nature of lines, curves and shapes within this three dimensional space? I've done a bunch of on line research here actually, and believe I have a good understanding of Einstein's introduction of the fourth dimension yielding spacetime of course, but it's not clear at all what Descartes actually added to Euclid's model, despite my understanding of what Cartesian coordinate systems are.