Well, I got back and I… I got sort of restless, you know, I was… I was back in Philadelphia, I came back to Fox Chase, and I decided I'd never done much undergraduate teaching, so—I had taught graduate students at Penn pretty regularly and I had quite a few whom  had their PhD in our lab there, and I taught the medical school when I went on rounds and all that, but I hadn't done any undergraduate teaching and I thought, okay, at my age it's probably a good thing to take a stab at that and I had… I knew Stanford quite well because for years we used to go there in the summer and… and work at the… the Center for Advanced Study and the Behavioral Sciences, which is a kind of behavioral sciences think tank. They usually had a few scientists there and I went there and would write, or… or very often spend a month making plans for future research. I… I would design, in detail, potential studies which, when it came back, you know, there'd be a big discussion, but very often it would initiate research. But I used to go there, so I knew that area quite well and it's a… a nice place to be in the… in the summer, or in the winter for that matter. So I taught in the program in human biology which had been established some years prior to that and… and, you know, interacting with the undergraduates was fun and I liked living in… I've always liked living in California. When… when I was, let me see, about 25 or so, I spent a summer at the… at the… in Berkley at the… before, you know, Berkley was still a quiet university town before all the festivities of the 1960s, but I got to know the… the geography well and I did a lot of climbing up in the Sierras and the Cascades and coast range and I… I hiked miles and miles then.