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 to lose a direct acqaintance with the actual and the individual, in the splendid theory of the possible.

The world of speculative reason differs from the actual world of living men, for man, as he is, differs from man as he ought to be. Philosophical theories are the nourishment of the purely rational principle; but they tend, unless the influence is counteracted by strength of mind, and an attentive observation of the infinite variety of the existing modifications of the instincts, affections, and other irrational causes of action, to deaden, or at least to distort, the keen perception of the common mechanism of man’s practical nature; and they may in this way expose the retired student of abstract metaphysics, like the astronomer of Rasselas who fancied that he ruled the stars, to the influence of ludicrous, or even of dangerous illusions, in the conduct of life, and in intercourse with living men. The machinery of society is regulated in a great measure by habits and desires, that are only indirectly, if at all, influenced by the operations of the understanding. The moving world of human beings often does not coincide with the hypotheses of human reasoning, while there exists in it much that cannot fail to be overlooked by the man of mere contemplation. His dreams are thus broken, from time to time, by unexpected collisions with living society, and by contact with modes of character which his speculations had not prepared him to expect.

It may be added that, except in the highest order of minds, this excessive development of the scientific faculty —this truth-seeking, only for the sake of knowing truth