The first person I met when I arrived in Oxford in 1975 to study Philosophy, Politics and Economics was Isaiah Berlin. Isaiah was a personal friend of one of my professors at the University of Toronto, who had asked Isaiah if, as a personal favour, he would serve as my "moral tutor". This rather quaint Oxford version of an "academic advisor" turned out, in my case, to be a profoundly apt term for the role that Berlin was to play in my intellectual development.