To prevent the chance of any misunderstanding, some explanation may be necessary for the benefit of those who are not in touch with scientific thought, and who hear that "Darwinism" is out of date. They should understand that, although the doctrine of Evolution as applied to organic life used to be widely spoken of by the term "Darwinism," the latter is now only used by scientists in a special sense, to designate the belief in the gradual origin of species by natural selection. There are some who deem this hypothesis to be untenable. But there is no dispute whatever concerning the doctrine of the derivation or descent, with modification, of all existing species, genera, orders, classes, etc., of animals and plants, from a few simple forms of life, if not from one. Modern evolutionary theories, however, are more particularly concerned with the question of the ways and means by which living organisms have assumed their actual characters or forms, and on these points there are many shades of individual opinion. Ignorance of the gist of the Darwinian theory, "natural selection," [135] has been fruitful in misunderstandings and objections regarding it, so that it is advisable to mention here that the author of the theory states explicitly that it does not account for the origin of variations in individuals, still less in species; but that, given the origination and existence of variations, it shows that some of these are preserved, while others are not--that favourable variations tend to be perpetuated, and unfavourable variations to become extinct; that those variations which best adapt an organisation to its environment are most favourable to its preservation, and, consequently, that the theory of natural selection is adequate to explain the observed fact of the survival of the fittest in the struggle for existence. "Natural selection ... implies that the individuals which are best fitted for the complex and changing conditions to which, in the course of ages, they are exposed, generally survive and procreate their kind." [136] Natural selection does not, it may be added, imply conscious selection. It would be equally true to call it natural murder, or natural weeding-out. But, whether Darwin and Weismann be right or wrong in attributing so much to natural selection, what I wish particularly to point out is that the hypothesis of Evolution is nowise invalidated because, out of the various causes at work, we are not quite sure as yet which is the most efficient. It is necessary to make this clear, for, hearing that "Darwinism" is under dispute, the uninitiated might come to the conclusion that the animal origin of man is discredited. THE AVERAGE PERSON'S IDEAS ON THE EVOLUTION OF MAN.