James Henle, Myra M. Sampson Professor Emeritus of Mathematics & Statistics from Smith College will deliver his lecture "Truth Has Gone Missing."

Preview of the lecture:  In the last century it was discovered that there are mathematical statements which can't be proved and can't be disproved. In the absence of proof, how can mathematicians determine what is true and what is false?  Indeed, does truth, in an absolute sense, exist?  Are there mathematical statements which are neither true nor false?

The problem has roots in the mathematics of ancient Greece.  My talk will trace the problem's path in mathematical history to the present, including the recent brilliant forays of Hugh Woodin. I'll discuss the fracturing of the philosophical landscape---the true believers, the agnostics, the fundamentalists, and the puzzled mathematical public.  It's an exciting time to do mathematics.  For some, it's an existential crisis.  For others, it's a time to play.