Discussing the notes Ludwig Wittgenstein made at the end of his life in 1951 that were published as On Certainty in 1969. Can we coherently doubt propositions like "physical objects exist," "the world is more than 50 years old," and "this is my hand"? Wittgenstein looks at these questions via his framework of language games. Is doubting one of these a legitimate move in a game? Get more at partiallyexaminedlife.com. Visit partiallyexaminedlife.com/support to get ad-free episodes and tons of bonus discussion. Check out the Overthink podcast and Conversations with Coleman. Attend our live show in NYC on April 15.