Why Did Lagrange Prove the Parallel Postulate?

Start: 09/19/2007 - 3:00pm
End  : 09/19/2007 - 5:00pm


Dr. Judith Grabiner (Pitzer College)


In 1806, Joseph-Louis Lagrange (1736-1813) read a memoir proving Euclid's parallel postulate to the Institut de France in Paris, but stopped, as the story goes, saying "I have to think about this some more." We'll look at Lagrange's still unpublished Paris manuscript on this subject, and place this activity in the context of his mathematical career. We will look also at how the ideas in this manuscript are related to Lagrange's philosophy of mathematics, Newton's physics, and Leibniz's Principle of Sufficient Reason. Finally, we will reflect on what this episode tells us about eighteenth-century attitudes toward geometry, space, and the universe.

Seaver North Auditorium 645 N. College Avenue, Pomona College

Misc. Information

Coffee & cookies at 4:00 p.m.
Wine and cheese after the talk, Harry Mullikin Room, Millikan 209

The dinner will be hosted by Jim Hoste. If interested in attending, call Ext. 73258