Natural Selection and Tropical Nature: Essays on Descriptive and Theoretical Biology

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Macmillan and Company, 1891 - 492 pages
 

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Page 207 - ... be said to be the result of the molecular forces of the protoplasm which displays it. And if so, it must be true, in the same sense and to the same extent, that the thoughts to which I am now giving utterance, and your thoughts regarding them, are the expression of molecular changes in that matter of life which is the source of our other vital phenomena.
Page 212 - WILL, while we have no knowledge of any other primary cause of force, it does not seem an improbable conclusion that all force may be will-force ; and thus, that the whole universe, is not \ merely dependent on, but actually is, the WILL of higher intelligences or of one Supreme Intelligence.
Page 26 - It seems evident that what takes place among the individuals of a species must also occur among the several allied species of a group, — viz., that those which are best adapted to obtain a regular supply of food, and to defend themselves against the attacks of their enemies and the vicissitudes of the seasons, must necessarily obtain and preserve a superiority in population; while those species which from some defect of power or organization are the least capable of counteracting the vicissitudes...
Page 35 - Darwin so earnestly impresses upon us, and which is indeed a necessary deduction from the theory of Natural Selection, namely — that none of the definite facts of organic nature, no special organ, no characteristic form or marking, no peculiarities of instinct or of habit, no relations between species or between groups of species — can exist, but which must now be or once have been useful to the individuals or the races which possess them.
Page 33 - ... to follow. An origin such as is here advocated will also agree with the peculiar character of the modifications of form and structure which obtain in organized beings — the many lines of divergence from a central type, the increasing efficiency and power of a particular organ through a succession of allied species, and the remarkable persistence of unimportant parts such as colour, texture of plumage and hair, form of horns or crests, through a series of species differing considerably in more...
Page 206 - ... to the other. They appear together, but we do not know why. Were our minds and senses so expanded, strengthened, and illuminated as to enable us to see and feel the very molecules of the brain ; were we capable of following all their motions, all their groupings, all their electric discharges, if such there be ; and were we intimately acquainted with the corresponding states of thought and feeling, we should be as far as ever from the solution of the problem, " How are these physical processes...
Page 156 - Strictly speaking, therefore, Mr. Darwin's theory is not a theory on the Origin of Species at all, but only a theory on the causes which lead to the relative success or failure of such new forms as may be born into the world.
Page 18 - Every species has come into existence coincident both in time and space with a preexisting closely allied species," Connects together and renders intelligible a vast number of independent and hitherto unexplained facts.
Page 277 - As the laws of Nature must be the same for all beings, the conclusions furnished by this group of insects must be applicable to the whole organic world; therefore, the study of butterflies — creatures selected as the types of airiness and frivolity — instead of being despised, will some day be valued as one of the most important branches of Biological science.
Page 206 - ... the passage from the current to the needle, if not demonstrable, is thinkable, and that we entertain no doubt as to the final mechanical solution of the problem. But the passage from the physics of the brain to the corresponding facts of consciousness is unthinkable.

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