We often say that something like winning the lottery is a miracle, when we really mean that it has a low, but actual, probability of occurring to us. But in 1748, philosopher David Hume argued against the existence of true miracles — events which could only be explained by defying the physical laws of nature. The question might seem settled, but in fact the debate surrounding miracles is a subject of contemporary philosophical research. Here, UW Professor of Philosophy Larry Shapiro asks whether it is possible to rationally believe in true miracles.