Evolution has nothing to do with such questions: it is a simple theory as to the mode of generation and order of succession of different forms of existences.
It is, however, when his lordship comes to discuss the doctrine of the survival of the fittest that his sad want of acquaintance with the whole subject shows itself most conspicuously. Let me quote: "By some means or other 'the survival of the fittest in the struggle for existence' is assumed to be a law of Nature, and if it be so our faith is severely taxed. Survival of the fittest—fittest for what? If the answer be, fittest for surviving, we argue in a circle, and get no information whatever. The only rational answer must be, they survive who are fittest for their environments in size, strength, and vigor." Let me here ask what sense the learned author can possibly attach to these last wordsthe very one he had just discarded as meaningless—"fitness to survive"? How is fitness to environment proved except by the actual fact of survival? Do environments always require "size" as an element of fitness? By no means, they sometimes require smallness. When a mouse escapes into a hole, where the cat can not follow, it survives not by reason of its size, but by reason of its smallness. Strength, again, is one element of adaptation to environment, but only one; and it may fall far below some other element, swiftness, for example, or cunning, in practical importance. The fact, however, that the learned author sees no meaning in the answer "fitness to survive," tells the whole story of his own unfitness for the special environment in which he has placed himself in attempting to discuss the doctrine of evolution, and rather tends to create doubt as to the survival of the work he has given to the world. This is a matter in which no aptitude in quoting Horace is of any avail. The road to an understanding of the terms and conceptions of modern science lies in a careful study at first hand of the works in which these terms and conceptions are expounded. His lordship assumes that, if we say that those survive who are fit to survive, we utter a barren truism. It is a truism we may grant, but not a barren one, any more than the axioms of geometry are barren. The simple word "fitness" implies a definite external something, adaptation to which is the price of existence. The definiteness of the mold involves the definiteness of that which is molded; and all the miracles of life and organization we see around us are in the last resort merely examples of adaptation to fixed conditions of existence. "Born into life we are," says Matthew Arnold, "and life must be our mold." By "life" understand the universe, and we have a poetical version of the doctrine of the survival of the fittest. It so happens, and this is a further truth which it would not be well to pass over, that adaptation does more or less imply excellence even from the human stand-point. All those adaptations that favor human life and happiness we of course call excellent, even though they may not be favorable to the life and happiness of other living creatures. And as