This article from the magazine _The Economist_ argues that the notion of mathematical proof is now in flux and that "the use of computers to prove mathematical theorems is forcing mathematicians to re-examine the foundations of their discipline." The author discusses the differences between proofs conducted by hand and those conducted by computers, using the classification of finite simple groups as an example showing how some proofs are unverifiable. The article concludes with a discussion of two recent examples illustrating how computers have been used to prove important mathematical results in a changing field.