perhaps not too much to say that every geological formation on the face of the globe is either wholly or in part due to the selective influence of specific gravity, and who shall say that the construction of the earth's crust is a less important matter in the general scheme of things (if there is such a scheme) than is the evolution of an eye? Or who shall say that because we see an apparently intentional adaptation of means to ends as the result of selection in the case of the eye, there is no intention served by the result of selection in the case of the sea-weeds, stones, sand, mud? For anything that we can know to the contrary, the supposed intelligence may take a greater delight in the latter than in the former process. For the sake of clearness I have assumed that the physical causes with which we are already acquainted are sufficient to explain the observed phenomena of organic nature. But it clearly makes no difference whether or not this assumption is conceded, provided we allow that the observed phenomena are all due to physical causes of some kind, be they known or unknown. That is to say, in whatever measure we exclude the hypothesis of the direct or immediate intervention of the Deity in organic nature (miracle), in that measure we are reducing the evidence of design in organic nature to precisely the same logical position as that which is occupied by the evidence of design in inorganic nature. Hence I conceive that Mill has shown a singular want of penetration where, after observing with reference to natural selection, 'creative forethought is not absolutely the only link by which the origin of the wonderful mechanism of the eye may be connected with the fact of sight,' he goes on to say, 'leaving this remarkable speculation (i.e. that of natural selection) to whatever fate the progress of discovery may have in store for it, in the present state of knowledge the adaptations in nature afford a large balance of probability in favour of creation by intelligence.' I say this passage seems to me to show a singular want of penetration, and I say so because it appears to argue that the issue lies between the hypothesis of special design and the hypothesis of natural selection. But it does not do so. The issue really lies between special design and natural causes. Survival of the fittest is one of these causes which has been suggested, and shown by a large accumulation of evidence to be probably a true cause. But even if it were to be disproved as a cause, the real argumentative position of teleology would not thereby be effected, unless we were to conclude that there can be no other causes of a secondary or physical kind concerned in the production of the observed adaptations.