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; Graham and I originating most of the novelties, while Grote and others furnished an excellent tribunal or test.

From this time I formed the project of writing a book on Logic, though on a much humbler scale than the one I ultimately executed.
Having done with Logic, we launched into Analytic Psychology, and having chosen Hartley for our text-book, we raised Priestley's edition to an extravagant price by searching through London to furnish each of us with a copy.

When we had finished Hartley, we suspended our meetings; but my father's _Analysis of the Mind_ being published soon after, we reassembled for the purpose of reading it.