Meditations on First Philosophy

Descartes goes about trying to decide, if all beliefs are eliminated, what indisputable truths remain? He goes very quickly from “I can't be sure I'm not just a brain in a vat” to “God definitely exists”. It's a fascinating and immensely flawed exercise. He references simple mathematics a bit (of course) and it seemed to me that his exploration was not dissimilar from Euclid's Elements but in the Euclid, he starts with assuming there are five axioms. If you change those axioms, you end up with an entirely different geometry. In this case, Descartes belief in God feels more like an axiom than a derived truth. So his declaration of rational truths could be said to be Descartian God truth, with the existence of a deity as an axiom and ostensibly a different set of truths could easily be derived by assuming the non-existence of God. It was a fun short read but by the end it became a slight slog since the “reality” that was being discussed did not feel convincing.