We love and hate them, but we can't escape them either — we're all obliged to live and work in buildings, and we all have strong feelings about how they look, how they function, and how they affect us. Witold Rybczynski plays architecture tour guide to explore some big questions: What makes buildings work (or not)? What were the architects thinking? And what do buildings tell us about ourselves, our times and what we do? Canadian architect Witold Rybczynski has thought long and hard about buildings — he's spent a lifetime teaching at the University of Pennsylvania. He joined Philip Coulter on a winter walking tour of the University of Pennsylvania campus to talk about how architecture works. His most recent book is called How Architecture Works: A Humanist's Toolkit.