Does science have all the answers? The answer is no, and the proof comes from science itself. Noson Yanofsky and I talked about his latest book, The Outer Limits of Reason: What Science, Mathematics, and Logic Cannot Tell Us. It's a treasury of insoluble problems, undecidable propositions and practical or theoretical barriers to understanding. We discussed Alan Turing's Halting Problem, Gödel's Incompleteness Theorem, Heisenbergian uncertainty, the mathematics of infinity and the simultaneously simple and ridiculously difficult traveling salesman problem. Also quantum computing, the trouble with self-referentiality and the wondrous correspondence between math and the physical world.