Page:Popular Science Monthly Volume 38.djvu/810

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which agnosticism repudiates than Prof. Huxley himself in his purely scientific writings. In his descriptions of the growth of living things, from the ovum to the finished creature, we seem to be listening to a literal reading and exposition of some page out of that book in which all "our members were written when as yet there were none of them." It is surely remarkable that Nature should be so full of the spirit and of the characteristic ideas of Hebrew and of Christian theology. But so it is. In Prof. Huxley's instructive work on the Elements of Comparative Anatomy he is rich in the use of language descriptive of the preparations for that which is to be. Every change that arises in the mysterious egg-substance is explained, as it can only be explained, by its relations with the future. Does a movement begin in the formless mass, establishing a long cleft or groove? It indicates the position "of the future longitudinal axis of the body." Do the lateral boundaries of this groove at one end of it "grow up into plates"? It is that this end is the end which "will become" the interior region of the body, and these plates are the "dorsal laminae." Do these dorsal laminæ at length unite? It is that they may "inclose the future cerebro-spinal cavity." Does another portion of the mass grow downward instead of up? It is that it may "form the vertical laminæ," with a function in the future not less essential.[1] One thing can only be understood when it is conceived as "laying the foundations" of another.[2] A second thing can only be understood as "pre-shadowing" the form and relations[3] of a third, and so on throughout. Nor does Prof. Huxley confine this great principle of interpretation to the development of the individual fœtus. This governing idea of referring all organic growth to the work of preparation and prevision, he extends to the whole history of life since it first began. He quotes with approbation, and adopts, the grand generalization of John Hunter, that organization is not the cause of life, but life is the cause of organization. Immense consequences are involved in this conception. Organisms are the habitations and the homes of life, but life must build them before it can settle in them and take possession. An organ is a structure for the discharge of function, but it must be shaped and made before the function can be discharged. This luminous idea sends its searching light through and through the stupidities which confound between things made for use and things that are said to be made by use. Use as an intellectual aim must precede use as a physical cause. And so the prophetic interpretation of fœtal development becomes the only possible interpretation of all organic growth so far as it is known to us. Accordingly, Prof. Huxley interprets the whole his-

  1. Pages 65, 66.
  2. Page 137.
  3. Page 142.