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partially folded inwards; and this contraction of the area is constantly resorted to. But a bird which has wings so small and scanty as to compel it to strike them always at full stretch, and with great velocity in order to fly at all, is incapable of standing still in the air. No man ever saw a Diver or a Duck performing the evolution which the Kestrel may be seen performing every hour over so many English fields. The cause of this is obvious if we refer to the principles which have already
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They are greatly assisted in this beautiful evolution by an adverse current of air; and it will always be observed that the Kestrel, when hovering, turns his head to wind, and hangs his whole body at a greater or less angle to the plane of the horizon. When there is no wind, or very little, the sustaining force is kept up by a short rapid action of the pinions, and the long tail is spread out like a fan to assist in stopping any tendency to onward motion. When there is a strong breeze, no
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lateral motion whatever. It does, indeed, materially assist the bird in turning, because it serves to stop the way of a bird when it rises or turns in the air to take a new direction. It contributes also largely to the general balance of the body, which in itself is an important element in the facility of flight. Accordingly, almost all birds which depend on great ease of evolution in flight or on the power of stopping suddenly, have largely developed tails. This is the case with all the birds
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in the sense in which Law is applied to an observed Order of facts. But like every other Order of this kind, it implies a, Force or an arrangement of Forces out of which the Order comes. It implies, too, that this arrangement of Forces is necessary to the evolution and play of mental faculties in the form in which they are possessed by us. Consequently these faculties are seen taking their place among all the other phenomena of the world. They are seen to be under the Reign of Law in this
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F2098
Book contribution:
Conway, Moncure Daniel. 1905. [Recollection of Darwin in 1867]. In Conway. Autobiography: memories and experiences. 2 vols. London: Cassell and Co, vol. 2, pp. 324-7.
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contributed something to represent them visibly in the constitution of the head able to interpret them. I was soon with Darwin in the garden, which was in floral glory. He expressed satisfaction that I had been able to derive from evolution the hopeful religion set forth in my discourse, but I remember that he did not express agreement with it. He spoke pleasantly of W. J. Fox M. P., my predecessor at South Place (whom he well knew), and asked me about [Ralph Waldo] Emerson, whose writings
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F2098
Book contribution:
Conway, Moncure Daniel. 1905. [Recollection of Darwin in 1867]. In Conway. Autobiography: memories and experiences. 2 vols. London: Cassell and Co, vol. 2, pp. 324-7.
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Darwin and Emerson died at nearly the same time (April 20 and April 27, 1882). The relation of these two minds to each other and to their time is striking. In the year (1836) when Darwin abandoned theology to study nature, Emerson, having also abandoned theology, published his first book, Nature, whose theme is Evolution. It was a notable circumstance that on the death of these two men who have done away with supernaturalism, no voice of odium theologicum broke the homage of England and
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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various forms; while the initial differences becoming intensified by development under different conditions will yield the diversities. The evolution of organisms, like the evolution of crystals, or the evolution of islands and continents, is determined by laws inherent in the substances evolved, and by their relations to the medium in which the evolution takes place. This being so, we may priori affirm that the resultant forms will have a community strictly corresponding with the identity
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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separate them into kingdoms, classes, orders, genera, species. The resemblances are many, and close, because (1) the forms evolved had a similar elementary composition, and (2) their stages of evolution were determined by similar conditions; the diversities are many, because (1) the forms evolved had from the first some diversities in elementary composition, and (2) their stages of evolution have been determined under conditions, which, though similar in general, have varied in particulars
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of evolution, we cannot but admire the patient perseverance of a philosopher who has accumulated so vast an array of facts as those in the volumes before us, and who has displayed so much calmness in laying down his opinions, and so much forbearance in replying to the bitter personalities in which his opponents have indulged. The two portions of the present work, though they are both branches of the evolution argument, are, nevertheless, somewhat distinct. In the first volume the author takes up
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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in following the demonstrations of embryologists, how from the common starting-point of a selfmultiplying epithelial cell parts so diverse as hairs, nails, hoofs, scales, feathers, crystalline lens, and secreting glands may be evolved, or how from the homogeneous germinal membrane the complex organism will arise, there are very few among the scorners of the dead hypothesis who seem capable of generalising the principles which have destroyed it, or can conceive that the laws of Evolution apply as
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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their histories. In the preceding observations the object has simply been to show that the phenomena to be explained can be rationally conceived as resulting from gradual Evolution, whereas they cannot be rationally interpreted on any other hypothesis. And here it may be needful to say a word respecting Epigenesis. The Preformation hypothesis, which regarded every organism is a simple educt and not the product of a germ, was called by its advocates an evolution hypothesis meaning that the adult
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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question. If, therefore, I venture to propose the one to which long meditation has led me, it is with the diffidence natural to such an attempt, and with the hope that some good must issue from a more thorough discussion. A few sentences will prepare the way. The evolution of Life is the evolution of the special from the general, the complex from the simple. An organism rises in power as it ramifies into variety. From a homogeneous organic mass a complex structure is evolved by successive
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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demonstrable that special forms have arisen thus. But there is a secondary aspect of the question, namely, Are all organic forms related to each other by the bond of kinship, or are many of them only related by the similarity of their evolution? Haeckel, Mr. Darwin's thorough-going disciple, who emphatically affirms that there is no other explanation of morphological phenomena except the blood-relationship of organisms, admits that it is possible some other causes besides Natural Selection may be
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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antagonists, and so remove the great obstacles to the general acceptance of Evolution. That I incline to a multiplicity of origins, the reader has already seen; and it now remains for me briefly to justify that position. The view itself may be thus indicated. In lieu of conceiving all organic resemblances as the inheritance from a common source, and all the diversities as divergences from that source, it is more consistent to assume that the resemblances, though very often due to kinship, are very often
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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is assumed, in each of which some initial diversity prepared the way for subsequent differentiations; just as we know that between the ovum of a vertebrate and the ovum of an invertebrate, similar as they are, there is a diversity which manifests itself in their subsequent evolution. If Function is determined by Structure, and evolution is the product of the two, it is clear that the different directions in the lines of develop [page] 49
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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disposition to undervalue the immense part played in Biology by what will hereafter be known as the Lex Daruiniana; but only a desire to leave the doctrine of Evolution free to include the Struggle for Existence among other factors. There can be no doubt that Natural Selection (aided by some minor laws as, for example, Moritz Wagner's Law of Migration ),1 while it gives a sudden precision to parts of the evolution doctrine that were very vague, also gives a satisfactory explanation of the
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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the striking illustrations from embryology1 in proof of Kielmeyer's position that all existing organisms are modifications of a single type, all the stages of the lower types being indicated in the successive transformations of an embryo of the highest type; but a rigorous criticism showed that in this form the hypothesis was not tenable.2 The hypothesis put forth in the Vestiges, though it had the merit of connecting the organic evolution with the cosmical evolution, uniting the hypotheses of
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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contradiction to it, or are simply purposeless; many of them have no adaptation even to its embryonic state; whereas all show stamped on them the unmistakeable characters of ancestral adaptations and the progressions of Organic Evolution. What does the fact imply? There is not a single known example of an organism which is not developed out of simpler forms. Before it can attain the complex structure which distinguishes it, there must be an evolution of forms which distinguish the structures of
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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parts are not added on to the old parts as new formations, but evolved from them as transformations. The word Evolution, therefore, seems to me more descriptive of the process than Epigenesis. It is true that the organism is not preformed, but the course of its development is precisely the course which its parents formerly passed through. Thus it is the Invisible the course of development which is predetermined. 1 When the word Epigenesis is used, therefore, the reader will understand it to
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A604
Review:
Lewes, George Henry. 1868. Mr. Darwin's hypotheses. Fortnightly Review n.s. 3 (April, June); 353-73, 611-28, 4 (July), (November): 61-80, 492-509.
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presented themselves in very different animals, and therefore that these organs, although so closely resembling each other, are not due to ancestral influence, we can hardly refuse to extend to the whole organism what we have admitted of a particular organ; and thus the admission of the spontaneous evolution of closely-resembling organs carries with it the admission of the spontaneous evolution of closely-resembling organisms; that muscular tissue should, under certain similar conditions
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