I just received by snail mail the December 2010 issue of Physics Today. The whole issue is devoted to Subrahmanyan Chandrasekhar, marking the centenary of his birth. There is a fascinating and challenging article Some memories of Chandra by Robert Wald and four other scientists, including Roger Penrose. Wald states:
Of all the scientists I have met, Chandra had the highest standards for both intellectual rigor and personal integrity. He applied those standards most uncompromisingly to himself, but he also did not tolerate failings by others in such matters. He was particularly intolerant of scientists motivated primarily by the hope of receiving recognition from others rather than by a deep, inner conviction that their work was of importance and interest, whatever anyone else might think. He was equally intolerant of scientists who rested on their laurels or were otherwise lazy or sloppy, rather than applying their full intellectual efforts toward their work.