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 ; 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 Encyclopaedia Metropolitana, and finally the “Computatio sive Logica” of Hobbes. These books, dealt with in our manner, afforded a wide 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