To ascertain the truth, and to be led by reason not by impulse, that was Lyell's great aim. Sedgwick once[166] criticised his work in terms which, in one respect, seem to me curiously mistaken: "Lyell ... is an excellent and thoughtful writer, but not, I think, a great field observer ... his mind is essentially deductive not inductive." The former criticism, as has been already admitted, is just, but the latter, _pace tanti viri_, seems to me the reverse of the truth. Surely there never was a geologist whose habits and methods were more strictly inductive than Lyell's. He would spare no pains, and hardly any expense, to ascertain for himself what the facts were; he abstained from drawing any conclusion until he had accumulated a good store; he compared and marshalled them, and finally adopted the interpretation with which they seemed most accordant. This interpretation, however, would be modified, or even rejected, if new and important facts were discovered. Surely this is the method of induction; surely this is the mode of reasoning adopted by Darwin and by Newton, and even by Bacon himself. But Sedgwick, great man as he was, almost unrivalled in the field, more brilliant, though less persevering than Lyell, was not always quite free from prejudices; and it may be noted that he more than once stigmatises an opinion which he dislikes by declaring it not to be in accordance with inductive methods. Sir Joseph Hooker's judgment was far more accurate: "One of the most philosophical of geologists, and one of the best of men"[167]; or that of Charles Darwin himself: "The science of geology is enormously indebted to Lyell--more so, as I believe, than to any other man who ever lived."[168]