Tip 5

Foundationalism:
Starting with the Solid Blocks

But in order to understand these things more perfectly, we must here consider that the light of nature, or the faculty of knowledge which God has bestowed upon us, cannot possibly discover to us any object which is not true in as far as it is clear and distinct.

Picture building a LEGO tower. You need those solid base pieces first, right? Descartes says knowledge works the same.

Start with the unshakeable, clear truths and build up. No wobbly pieces allowed—only rock-solid blocks of certainty.