Read on its own, the First Meditation can be seen as presenting skeptical doubts as a subject of study in their own right. Certainly, skepticism is a much-discussed and hotly debated topic in philosophy, even today. Descartes raised the mystifying question of how we can claim to know with certainty anything about the world around us. The idea is not that these doubts are probable, but that their possibility can never be entirely ruled out. And if we can never be certain, how can we claim to know anything? Skepticism cuts straight to the heart of the Western philosophical enterprise and its attempt to provide a certain foundation for our knowledge and understanding of the world. It can even be pushed so far as to be read as a challenge to our very notion of rationality.