‘It represents the archetype, or primal pattern—what Plato would have called the “Divine Idea”—on which the osseous frame of all vertebrate animals has been constructed. The motto is “The One in the Manifold,” expressive of the unity of plan which may be traced through all the modifications of the pattern, by which it is adapted to the varied habits and modes of life of fishes, reptiles, birds, beasts, and human kind. Many have been the attempts to discover the vertebrate archetype, and it seems now generally felt that it has been found’ (i. 388).
But, assuming Owen to have really discovered the one, he was as far off as ever from the origin of the many. And on this subject he never did reach any definite conclusion. He admits, it is true, a theory which sounds very like evolution:
‘Thus, at the acquisition of facts adequate to test the moot question of links between past and present species, as at the close of that other series of researches proving the skeleton of all Vertebrates, and even of Man, to be the harmonized sum of a series of essentially similar segments, I have been led to recognize species as exemplifying the continuous operation of natural law, or secondary cause; and that, not only successively, but progressively; from the first embodiment of the Vertebrate idea under its old Ichthyic vestment until it became arrayed in the glorious garb of the human form[122].’
In this quotation he is in the main stating the views he held in 1849, for the latter portion of it is from his essay _On the Nature of Limbs_, published in that year. But the nature of the secondary cause which produced species cannot be concluded from his works. He fiercely contested Darwin’s theory of natural selection, both in conversation and in periodicals. To the last he clung to a notion of a ‘vital property,’ which is thus described in the _Anatomy_ (iii. 807):
‘So, being unable to accept the volitional hypothesis, or that of impulse from within, or the selective force exerted by outward circumstances, I deem an innate tendency to deviate from parental type, operating through periods of adequate duration, to be the most probable nature, or way of operation, of the secondary law, whereby species have been derived one from the other.’