Unfortunate it may be, but despite the spectacular successes of modern science, there is no ultimate foundation for our knowledge of the world. This was David Hume’s great insight, when he formulated his famous problem of induction. Hume realized that all knowledge about the world is ultimately derived from a process of induction, ie by generalization from specific instances to broader rules. But how do we know that induction works? Because it has worked in the past, obviously. Yet this itself is an example of inductive reasoning, which makes the justification of induction and science itself perilously circular.