This last difficulty remains my chiefest apprehension still. Neither in the Essay itself, nor yet in the additions made to it, have I introduced any one point which it seemed permissible to omit with justice to the real issue. Yet I dare not hope that many eyes, except those of the practised student, will easily perceive how germane to that issue are several among the subjects discussed. One class of thinkers will, however, welcome the whole of these inquiries; and this class contains the earnest men for whom above all others I have written. The amount of MS. sent to the Registrar was much less in compass than the present volume. But Notes and Illustrations were intended from the first, and, had there existed a doubt as to their propriety, it would have been at once removed by the counsel of competent advisers. The risks attaching to the Essay in its smaller shape were said to be two: (1) An evident appearance of unwilling brevity, and (2) a possible charge of novel thought, bordering on paradox. In attempting to overcome these obstacles to favourable attention, I have pursued the following course:-- The text of the Essay is printed as originally written, with only a very few verbal changes for the sake of improved clearness. A number of foot-notes belonging to its first draft, remain distinguished by the ordinary marks of reference.[2] In reperusing the text, I set myself to consider how many sympathisers I could find. The best answer to any possible charge of Paradox, seemed to be a roll-call of thinkers who, for their own purposes, have asserted positions more or less approaching those I had attempted to maintain. The number of auxiliaries I have thus succeeded in assembling, is, I confess, a matter of considerable self-gratulation. Yet, I do not appeal to such opinions as _authorities_, in any other sense than so far forth as they are the decisions of _experts_ in different provinces of knowledge. In whatever concerns his own department, each scientific worker has assuredly a right to be heard. The weight of confirmation thus given to my own previous results, is enhanced by the fact that most of the authors cited, pursued different objects from mine, and wrote without any bias favourable to Natural Theology. Respecting more than one of them, I feel inclined to repeat the ancient adage, "My antagonist has become my helper."