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p.72 I have called this principle, by which each slight variation, if useful, is preserved, by the term
Natural Selection, in order to mark its relation to man's power of selection. But the expression often used by Mr. Herbert
Spencer, of the Survival of the Fittest, is more accurate, and is sometimes equally convenient... Natural Selection, as we
shall hereafter see, is a power incessantly ready for action, and is immeasurably superior to man's feeble efforts, as the
works of Nature are to those of Art.
p.73,74 A struggle for existence inevitably follows from the high rate at which all organic beings tend
to increase... as more individuals are produced than can possibly survive, there must in every case be a struggle for existence,
either one individual with another of the same species, or with the individuals of distinct species, or with the physical
conditions of life... Although some species may be now increasing, more or less rapidly, in numbers, all cannot do so, for
the world would not hold them.
p.79,81,82 Many cases are on record showing how complex and unexpected are the checks and relations between
organic beings, which have to struggle together in the same country... I am tempted to give one more instance showing how
plants and animals, remote in the scale of nature, are bound together by a web of complex relations... In the case of every
species, many different checks, acting at different periods of life, and during different seasons or years, probably come
into play; some one check or some few being generally the most potent; but all will concur in determining the average number
or even the existence of the species
p.91 It may metaphorically be said that natural selection is daily and hourly scrutinizing, throughout
the world, the slightest variations; rejecting those that are bad, preserving and adding up all that are good; silently and
insensibly working, whenever and wherever opportunity offers, at the improvement of each organic being in relation
to its organic and inorganic conditions of life. We see nothing of these slow changes in progress, until the hand
of time has marked the lapse of ages, that we see only that the forms of life are now different from what they formerly were.
p.135 if variations useful to any organic being ever do occur, assuredly individuals thus characterized
will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance, these
will tend to produce offspring similarly characterized. This principle of preservation, or the survival of the fittest, I
have called Natural Selection.
p.151-152 Thus, I believe, natural selection will tend in the long run to reduce any part of the organisation,
as soon as it becomes, through changed habits, superfluous, without by any means causing some other part to be largely developed
in a corresponding degree. And, conversely, that natural selection may perfectly well succeed in largely developing an organ
without requiring as a necessary compensation the reduction of some adjoining part.
p.184 suppose that there is a power, represented by natural selection or the survival of the fittest,
always intently watching each slight alteration... and carefully preserving each which, under varied circumstances, in any
way or in any degree, tends to produce a distincter image [JLJ - Darwin is discussing the evolution of the
eye, but he might as well be discussing, in game theory, the selection and analysis of 'promising' moves, each
offering a slightly different way of developing the current position. We theorize that an evolutionary 'survival
of the fittest move' can guide our thinking as we form and prune the analysis tree. ] ... variation will
cause the slight alterations, generation [JLJ - new life arising and leaving offspring] will multiply them
almost infinitely, and natural selection will pick out with unerring skill each improvement.
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