ving 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
exposition came to be written, I found that I had so much over-estimated
my agreement with him, and he dissented so much from the most original
of the two Essays, that on International Values, that I was obliged to
consider the theory as now exclusively mine, and it came out as such
when published many years later. I may mention that among the
alterations which my father made in revising his _Elements_ for the
third edition, several were founded on criticisms elicited by these
conversations; and in particular he modified his opinions (though not to
the extent of our new speculations) on both the points to which I
have adverted.

When we had enough of political economy, we took up the syllogistic
logic in the same manner, Grote now joining us. Our first text-book was
Aldrich, but being disgusted with its superficiality, we reprinted one
of the most finished among the many manuals of the school logic, which
my father, a great collector of such books, possessed, the _Manuductio
ad Logicam_ of the Jesuit Du Trieu. After finishing this, we took up
Whately's _Logic_, then first republished from the _Encyclopedia
Metropolitana_, and finally the _Computatio sive Logica_ of Hobbes.
These books, dealt with in our manner, afforded a high range for
original metaphysical speculation: and most of what has been done in the
First Book of my _System of Logic_, to rationalize and correct the
principles and distinctions of the school logicians, and to improve the
theory of the Import of Propositions, had its origin in these
discussions; Grah