On October 25, 1946, in Cambridge, England, Ludwig Wittgenstein and Karl Popper came face-to-face for the first and only time. The encounter lasted just ten minutes, and did not go well. Their loud and aggressive confrontation became the stuff of instant legend. Almost immediately, rumors spread around the world that the two great philosophers had come to blows, armed with red-hot pokers. Twenty years later, when Popper wrote an account of the incident, he portrayed himself as the victor, provoking intense disagreement. Everyone present seems to have remembered events differently. What really happened in those ten minutes? And what does the violence of this brief exchange tell us about these two men, modern philosophy, and the significance of language in solving our philosophical problems? Wittgenstein's poker is an engaging mix of philosophy, history, biography, and literary detection.