In '64 I must say I returned to IBM and my feelings and my status and everything had changed radically. I was no longer, how should I say, dabbling in esoterica of various kinds, giving lectures which are amusing but nobody followed, but I had now done this work on prices which were at the very core of economics and this work on turbulence at the very core of fluid mechanics. Moreover very skilled, demanding and 'show me' individuals had become convinced that I had a path through the truth and I was able to go on. Each had to be enormously developed, because it was not a matter of picking up a book off the shelf that had a theory applicable to it, but in fact of doing it more or less from scratch. In particular, having listened to Paul Levy about the stable distribution and stable processes, I was aware of the Hausdorff dimension and realised that the Hausdorff dimension was something which was ready to move from esoterica to reality. I may add that I knew more about the Hausdorff dimension than just from Paul Levy. While I was a post-doc of Von Neumann I met a student at Princeton named H. J. McKean who later became a very famous mathematician, Henry had written a Ph.D. on the Hausdorff Besikovitch dimension of certain sets in probability theory. I was very surprised that a man as bright, as brilliant as Henry was worrying about this little esoteric exercise but this was my friend, I read his thesis, therefore I found out about this technique, which of course at that time I spurned very greatly. But again, for myself in '64, in the context of prices, the measurement of relativity was a Hausdorff dimension, or some other dimension like Hausdorff's. In the context of turbulence the measurement of roughness was again the Hausdorff dimension. Hausdorff dimension was coming into the centre of things.