Somewhat may be justly, or at least plausibly, said in reply to all this from the ordinary standpoint, but probably not to much effect. There were always insuperable difficulties, which, when they seemed to be few, might be regarded as exceptional; but, as they increase in number and variety, they seem to fall into a system. No doubt we may still insist that, “in the present state of our knowledge, the adaptations in Nature afford a large balance of probability in favor of creation by intelligence,” as Mill concluded; and probability must needs be the guide of reason through these dark places. Still, the balancing of irreconcilable facts is not a satisfying occupation, nor a wholly hopeful one, while fresh weights are from time to time dropping into the lighter side of the balance. Strong as our convictions are, they may be overborne by evidence. We cannot rival the fabled woman of Ephesus, who, beginning by carrying her calf from the day of its birth, was still able to do so when it became an ox. The burden which our fathers carried comfortably, with some adventitious help, has become too heavy for our shoulders.
Seriously, there must be something wrong in the position, some baleful error mixed with the truth, to which this contradiction of our inmost convictions may be attributed. The error, as we suppose, lies in the combination of the principle of design with the hypothesis of the immutability and isolated creation of species. The latter hypothesis, in its nature un-provable, has, on scientific grounds, become so far improbable that few, even of the anti-Darwinian naturalists, now hold to it; and, whatever may once have been its religious claims, it is at present a hinderance rather than a help to any just and consistent teleology.
By the adoption of the Darwinian hypothesis, or something like it, which we incline to favor, many of the difficulties are obviated, and others diminished. In the comprehensive and far-reaching teleology which may take the place of the former narrow conceptions, organs and even faculties, useless to the individual, find their explanation and reason of being. Either they have done service in the past, or they may do service in the future. They may have been essentially useful in one way in a past species, and, though now functionless, they may be turned to useful account in some very different way hereafter. In botany several cases come to our mind which suggest such interpretation.
Under this view, moreover, waste of life and material in organic Nature ceases to be utterly inexplicable, because it ceases to be objectless. It is seen to be a part of the general “economy of Nature,” a phrase which has a real meaning. One good illustration of it is furnished by the pollen of flowers. The seeming waste of this in a pine-forest is enormous. It gives rise to the so-called “showers of sulphur,” which every one has heard of. Myriads upon myriads of pollen-grains (each an elaborate organic structure)