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s answered in the affirmative; and arrives at this answer through the following conclusions. The English political economist Malthus (1766-1834), in his "Essay on the Principles of Population," established a law in regard to the growth of the human race, which may be applied just as well to all the species of the entire organic world: that population tends to increase in a geometrical ratio, although the conditions of life for the individual remain the same or at most increase in an arithmetical ratio. The consequence is that if the species is to be preserved and the individuals of future generations are to continue to find sufficient food and other means for sustaining life, a great many individuals of each generation must perish very early, and even as germ and seed, and only a minority will be preserved and reproduced. This exuberant prodigality of life-germs, of which proportionately only a few are preserved and reproduced, takes place in the plant and {40} animal world in a very marked degree. There a continual _struggle for existence_ prevails; each individual has to get access to his conditions of life by wresting them from a whole series of other individuals of his own or other species; and now the question arises: which individuals will survive in this struggle? which will more probably be preserved and procreate offspring? Evidently, the answer is, those individuals which possess individual characteristics more favorable to the preservation of the individual than those possessed by other individuals. These individual characteristics are transmitted to the next generation. In this there will be again individuals that have in a still higher degree the characteristics thus transmitted and favorable for the preservation of the individual, or that add to these favorable characteristics new characteristics favorable in another direction to the survival of the individual in the struggle for existence. While these individuals, with more probability than the others, are thus preserved and reproduced, they transmit to their offspring not only the old favorable characteristics increased, but also those newly added. Among the favorable individual qualities, Darwin reckons the divergence of character, the perfection of organization, and the law of correlation; the latter, however, can not be explained by natural selection, since according to this law a variation in an organ brings about a corresponding variation in entirely
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