Catholics and Evolution

Catholics and Evolution

One of the most important questions for every educated Catholic of today is: What is to be thought of the theory of evolution? Is it to be rejected as unfounded and inimical to Christianity, or is it to be accepted as an established theory altogether compatible with the principles of a Christian conception of the universe?

We must carefully distinguish between the different meanings of the words theory of evolution in order to give a clear and correct answer to this question. We must distinguish (1) between the theory of evolution as a scientific hypothesis and as a philosophical speculation; (2) between the theory of evolution as based on theistic principles and as based on a materialistic and atheistic foundation; (3) between the theory of evolution and Darwinism; (4) between the theory of evolution as applied to the vegetable and animal kingdoms and as applied to man.

(1) Scientific Hypothesis vs. Philosophical Speculation

As a scientific hypothesis, the theory of evolution seeks to determine the historical succession of the various species of plants and of animals on our earth, and, with the aid of palжontology and other sciences, such as comparative morphology, embryology, and bionomy, to show how in the course of the different geological epochs they gradually evolve from their beginnings by purely natural causes of specific development. The theory of evolution, then, as a scientific hypothesis, does not consider the present species of plants and of animals as forms directly created by God, but as the final result of an evolution from other species existing in former geological periods. Hence it is called "the theory of evolution", or "the theory of descent", since it implies the descent of the present from extinct species. This theory is opposed to the theory of constancy, which assumes the immutability of organic species. The scientific theory of evolution, therefore, does not concern itself with the origin of life. It merely inquires into the genetic relations of systematic species, genera, and families, and endeavours to arrange them according to natural series of descent (genetic trees).

How far is the theory of evolution based on observed facts? It is understood to be still only an hypothesis. The formation of new species is directly observed in but a few cases, and only with reference to such forms as are closely related to each other; for instance, the systematic species of the plant-genus Њnothera, and of the beetle-genus Dimarda. It is, however, not difficult to furnish an indirect proof of great probability for the genetic relation of many systematic species to each other and to fossil forms, as in the genetic development of the horse (Equidж), of ammonites, and of many insects, especially of those that dwell as "guests" with ants and termites, and have adapted themselves in many ways to their hosts. Upon comparing the scientific proofs for the probability of the theory of evolution, we find that they grow the more numerous and weighty, the smaller the circle of forms under consideration, but become weaker and weaker, if we include a greater number of forms, such as are comprised in a class or in a sub-kingdom. There is, in fact, no evidence whatever for the common genetic descent of all plants and animals from a single primitive organism. Hence the greater number of botanists and zoologists regard a polygenetic (polyphyletic) evolution as much more acceptable than a monogenetic (monophyletic). At present, however, it is impossible to decide how many independent genetic series must be assumed in the animal and vegetable kingdoms. This is the gist of the theory of evolution as a scientific hypothesis. It is in perfect agreement with the Christian conception of the universe; for Scripture does not tell us in what form the present species of plants and of animals were originally created by God. As early as 1877 Knabenbauer stated "that there is no objection, so far as faith is concerned, to assuming the descent of all plant and animal species from a few types" (Stimmen aus Maria Laach, XIII, p. 72).

Passing now to the theory of evolution as a philosophical speculation, the history of the plant and animal kingdoms upon our globe is but a small part of the history of the entire earth. Similarly, the geological development of our earth constitutes but a small part of the history of the solar system and of the universe. The theory of evolution as a philosophical conception considers the entire history of the cosmos as an harmonious development, brought about by natural laws. This conception is in agreement with the Christian view of the universe. God is the Creator of heaven and earth. If God produced the universe by a single creative act of His will, then its natural development by laws implanted in it by the Creator is to the greater glory of His Divine power and wisdom. St. Thomas says: "The potency of a cause is the greater, the more remote the effects to which it extends." (Summa c. Gent., III, c. lxxvi); and Suarez: "God does not interfere directly with the natural order, where secondary causes suffice to produce the intended effect" (De opere sex dierum, II, c. x, n. 13). In the light of this principle of the Christian interpretation of nature, the history of the animal and vegetable kingdoms on our planet is, as it were, a versicle in a