Some Philosophical Considerations on Biological Evolution

THE THOMIST A SPECULATIVE QUARTERLY REVIEW OF THEOLOGY AND PHILOSOPHY EDITORS: THE DoMINICAN FATHERS oF THE PROVINCE oF ST. JosEPH Publishers: The Thomist Press, Washington, D. C. ~0017 VoL. XXXVII JULY, 1973 No.3 SOME PHILOSOPHICAL CONSIDERATIONS ON BIOLOGICAL EVOLUTION THE PROBLEM of biological evolution, as we understand it now, appeared in the 19th century as a consequence of scientific data totally unknown to philosophers and theologians before Darwin. It makes little sense, therefore, to search for this problem in the writings of St. Thomas. Sharing the opinion common to his time, he believed the universe to be no more than 6,000 years old. The ancient theologians did, however, discuss a type of evolution ; that is, that the universe was created in six days. St. Augustine, for example, maintained that all six days were one since God created all things simultaneously: the inorganic in act, that is, in their present state; and the organic in potency, namely, in their quasi-seminal state. Plants and animals were implanted in the world "after the manner of seed (tamquam seminaliter mundo indita) by virtue of the Word of God when he created all things simultaneously, and from which all things, 417 418 ANTONIO MORENO each in its proper time, would be drawn in the course of the ages." 1 According to other saints the six days of Genesis denoted the order of time and succession in creation. There was an order not only of nature but also of time and duration in the work of the six days. This latter opinion held that various creatures were produced successively, whereas St. Augustine believed that all was created instantly. Whereas the latter interpretation emphasized the creative power of God through the passage of time, St. Augustine taught that God created the whole world instantaneously-if not entirely in act at least in potency. For St. Augustine, the world, bit by bit, was transformed into actuality.2 It is most significant that St. Thomas simultaneously accepted both interpretations: The first explanation of these things, namely, that held by St. Augustine, is the more subtle and is a better defense of Scripture against the ridicule of unbelievers; but the second which is maintained by the other saints is easier to grasp and more in keeping with the surface meaning of the text. Seeing, however, that neither is in contradiction with the truth of faith and that the context 1 St. Augustine De Gen. ad litt. 6. 5, 8; ML 34, 342. Cf. ibid., 4, 33, 52; ML 34, 318: "God created all things simultaneously." Ibid., 5, 4, 11; ML 34, 325: " Therefore, it has been said that then the earth produced the herb and the plant in their causes, that they received the power to produce. For in it were already, as it were in their roots of times, those things that were to come about in future times ..." Ibid., 5, 5, 14; ML 34, 326: In reference to animals St. Augustine says: " ...all the swimming creatures and the flying creatures and these also potentially in numbers, which would come forth in their proper cycles in time. Similarly the animals of earth, as if the last from the last element of the world; nevertheless potentially, whose numbers time would manifest visibly." • St. Thomas, On the Power of God, q. 4, a. 2. Cf. ibid., ad 28: " ...the plants were brought forth then, not into actual existence but only in certain seed-forms, inasmuch as the earth enabled to produce them. . . . Hence the plants were not actually produced on the third day but only in their causes: and after the six days they were brought into actual existence in their respective species and natures by the work of government. Consequently, before the plants were produced causally nothing was produced, but they were produced together with the heaven and the earth. In like manner the fishes, birds, and animals were produced in those days causally and not actually. " CONSIDERATIONS ON BIOLOGICAL EVOLUTION 419 admits of either intepretation, in order that neither may be unduly favored, we now proceed to deal with the arguments of either side.3 A gradual appearance in time of the different genera and species...