inherited. At least, Darwin did not distinguish clearly between those char- 

 acteristics that are inherited and those that are not. As in the case of Lamarck's 

 assumption, this is not a matter of opinion; and the facts in the case were not 

 known in Darwin's time. 



The second assumption is that the destruction of living things is in most 

 cases selective. That is, that individuals generally die because of some heritable 

 disadvantage, as compared with those who survive in the same circumstances. 

 There are about every plant and animal multitudes of details that distinguish 

 it from closely related species but that can have no conceivable bearing upon 

 survival. Moreover, vast numbers of individuals are destroyed indiscrimi- 

 nately by floods, fires, general drought, and so on, with only a few survivors 

 remaining, largely through chance. 



Darwin's theory may explain the extinction of some strains and the sur- 

 vival of others; but it has no suggestion as to how new characters arose in the 

 first place. If we grant that variations in degree of fitness influence the sur- 

 vival of types, we have remaining the question of origin: How do new char- 

 acteristics originate? Darwin was aware of this difficulty, as appears in his 

 book The Origin of Species: 



Several writers have misapprehended or objected to the term Natural Selection. 

 Some have even imagined that natural selection induces variability, whereas it 

 implies only the preservation of such variations as arise and are beneficial to the 

 being under its conditions of life. No one objects to agriculturists speaking of the 

 potent effects of man's selection; and in this case the individual differences given 

 by nature, which man for some object selects, must of necessity first occur. Others 

 have objected that the term selection implies conscious choice in the animals which 

 become modified; and it has even been urged that, as plants have no volition, 

 natural selection is not applicable to them! In the literal sense of the word, no 

 doubt, natural selection is a false term; but who ever objected to chemists speak- 

 ing of the elective affinities of the various elements? — and yet an acid cannot 

 strictly be said to elect the base with which it in preference combines. It has been 

 said that I speak of natural selection as an active power or Deity; but who objects 

 to an author speaking of the attraction of gravity as ruling the movements of the 

 planets? Every one knows what is meant and is implied by such metaphorical 

 expressions; and they are almost necessary for brevity. So again it is difficult to 

 avoid personifying the word Nature; but I mean by Nature, only the aggregate 

 action and product of many natural laws, and by laws the sequence of events as 

 ascertained by us. With a Httle familiarity such superficial objections will be 

 forgotten. 1 



The difficulty that all these explanations have in common seems to come 

 from trying to reconcile two unquestionable facts: (1) Like produces like, 

 and (2) Species inhabiting the earth today are dirferent from the species that 

 lived in the past. 



^The italics are ours, not Darwin's. 

 468 



