That the great advancing movement of life has been a divergence, an opening out, or an evolution, is incontestable, and is admitted by the highest biological authorities. It is proved by the fact that, if we go back a million of years or so, there is an obvious convergence of types, or the different kinds of animals will have to be represented as nearer together in characters, and, as we recede still farther into the past, the approximation becomes still closer. Prof. Owen says he has "never omitted a proper opportunity for impressing the results of observations showing the more generalized structures of extinct, as compared with the more specialized form of recent animals." Prof. Agassiz takes a similar position, insisting strongly that "The more ancient animals resemble the embryonic forms of existing species." Mr. Wallace says: "As we go back into past time and meet with the fossil remains of more and more ancient races of extinct animals we find that many of them actually are intermediate between distinct groups of existing animals." Prof. Cope remarks: "That the existing state of the geological record of organic types should be regarded as any thing but a fragment is, from our stand-point, quite preposterous. And more, it may be assumed with safety, that when completed, it will furnish us with a series of regular successions, with but slight and regular interruptions, if any, from the species which represented the simplest beginnings of life at the dawn of creation, to those which have displayed complication and power in a later or in the present period. For the labors of the paleontologist are daily bringing to light structures intermediate between those never before so connected, thus creating lines of succession where before were only interruptions." Is the great conclusion of an unfolding method in the order of life which is based upon a vast body of biological facts, and supported by the powerful analogies of an unfolding order in other parts of nature, to be characterized as a high-flown a priori speculation? or is it a result of strict inductive inquiry, which replaces an a priori hypothesis of life that prevailed for ages before science had entered upon its study?
Again, humanity is not now what it was in ages long past. That man's existence upon earth dates back to a far profounder antiquity than has formerly been believed, is a clear induction from an extensive array of facts. Be the time longer or shorter, an immense series of changes has taken place in the history of the race. A few thousand years ago Europe was barbarous, and its inhabitants warred and worked with implements of stone. Society was rude, low, homogeneous, and undeveloped. Its movement has been a slow unfolding into diversity and specialty. There has been an increase of human capabilities, a rise in intelligence, an advance of morals, a growing capacity of social cooperation, a multiplication of arts and industries, augmented power over Nature, an emergence of institutions, and in short an evolution of civilization. This is a broad induction, from the facts of history, from the facts of prehistoric archæology, and from the facts of anthropology, and it is fast taking the place of the old a priori speculation that the course of humanity has been a degeneracy, and which was firmly believed until science reversed the method of studying the subject.
Sir Charles Lyell, it will hardly be denied, is one of the most learned and able of living geologists. His painstaking conscientiousness as an observer and his judicial caution and calmness as an inductive reasoner are beyond question. For fifty years he has studied the subject of life in connection with the past changes of the globe, and has embodied his conclusions in his various geological works. In the earlier of