Originally posted by Paul Dirac IIYeah, only three. I was confusing that one with a 4 volume set on math I got at a yard sale.
Somewhere around the house I've got three volumes, red softcover.
Maybe a fourth volume came out in the last 30 years?
Here is a link to a lot of feynman stuff including the lectures:
http://www.feynmanlectures.info/
Besides Feynman, there are a series of great links, check them out.