1. In revising this terminal division of my former second volume, I find less to be corrected or condemned than in the previous chapters; but far more, were it conveniently now possible, to be supplied. The treatment of this part of the subject is not only incomplete, but involves the omission of all the most important practical questions in the useless curiosity of analysis, just as a common anatomist describes the action of muscles in walking, without thereby helping anybody to walk, or those of a bird's wing in flying, without defining the angles of its stroke to the air. I have thus examined at tedious length the various actions of human conception and memory, without helping any one to conceive, or to remember; and, at least in this part of the book, scarcely touching at all on the primary questions (both moral and intellectual) how far the will has power over the imagination. It was perhaps in reality fortunate that I should not have entered on these higher inquiries till I was older and more experienced; nor shall I now attempt to remedy such defects by hasty patching of the text or fortuitous addition of notes to it. One or two introductory observations may, however, make this imperfect essay more useful, so far as it reaches.