While thus engaged in writing for the public, I did not neglect other modes of self-cultivation. It was at this time that I learnt German; beginning it on the Hamiltonian method, for which purpose I and several of my companions formed a class. For several years from this period, our social studies assumed a shape which contributed very much to my mental progress. The idea occurred to us of carrying on, by reading and conversation, a joint study of several of the branches of science which we wished to be masters of. We assembled to the number of a dozen or more. Mr. Grote lent a room of his house in Threadneedle Street for the purpose, and his partner, Prescott, one of the three original members of the Utilitarian Society, made one among us. We met two mornings in every week, from half-past eight till ten, at which hour most of us were called off to our daily occupations. Our first subject was Political Economy. We chose some systematic treatise as our text-book; my father's _Elements_ being our first choice. One of us read aloud a chapter, or some smaller portion of the book. The discussion was then opened, and anyone who had an objection, or other remark to make, made it. Our rule was to discuss thoroughly every point raised, whether great or small, prolonging the discussion until all who took part were satisfied with the conclusion they had individually arrived at; and to follow up every topic of collateral speculation which the chapter or the conversation suggested, never leaving it until we had untied every knot which we found. We repeatedly kept up the discussion of some one point for several weeks, thinking intently on it during the intervals of our meetings, and contriving solutions of the new difficulties which had risen up in the last morning's discussion. When we had finished in this way my father's _Elements_, we went in the same manner through Ricardo's _Principles of Political Economy_, and Bailey's _Dissertation on Value_. These close and vigorous discussions were not only improving in a high degree to those who took part in them, but brought out new views of some topics of abstract Political Economy. The theory of International Values which I afterwards published, emanated from these conversations, as did also the modified form of Ricardo's _Theory of Profits_, laid down in my _Essay on Profits and Interest_. Those among us with whom new speculations chiefly originated, were Ellis, Graham, and I; though others gave valuable aid to the discussions, especially Prescott and Roebuck, the one by his knowledge, the other by his dialectical acuteness. The theories of International Values and of Profits were excogitated and worked out in about equal proportions by myself and Graham: and if our original project had been executed, my _Essays on Some Unsettled Questions of Political Economy_ would have been brought out along with some papers of his, under our joint names. But when my