In my recent lecture on freedom I claimed that the true father of the modern conception of freedom is not one of the great political thinkers such as Hobbes or Locke or Rousseau, but rather the father of modern philosophy in general: Descartes. Descartes’s philosophy, backed up by the spectacular successes of the application of his new mathematics, gave dominance to a non-teleological account of nature. And therefore he and his many successors did not understand human freedom as the ability to understand given ends and to pursue them, but rather as a quasi-creative power, making those ends good which it chose. Thus a key question for settling which conception of freedom is right is the question of the which philosophy of nature is true: the teleological philosophy of nature in the tradition of Aristotle, or the so-called “mechanistic” natural science of the Cartesian tradition.
In the introduction to Natural Right and History Leo Strauss, showing his remarkable ability to go straight to the fundamental questions, presents the issue as follows:
Natural right in its classic form is connected with a teleological view of the universe. All natural beings have a natural end, a natural destiny, which determines what kind of operation is good for them. In the case of man, reason is required for discerning these operations: reason determines what is by nature right with ultimate regard to man’s natural end. The teleological view of the universe, of which the teleological view of man forms a part, would seem to have been destroyed by modem natural science. From the point of view of Aristotle— and who could dare to claim to be a better judge in this matter than Aristotle?— the issue between the mechanical and the teleological conception of the universe is decided by the manner in which the problem of the heavens, the heavenly bodies, and their motion is solved. Now in this respect, which from Aristotle’s own point of view was the decisive one, the issue seems to have been decided in favor of the non teleological conception of the universe. Two opposite conclusions could be drawn from this momentous decision. According to one, the nonteleological conception of the universe must be followed up by a nonteleological conception of human life. But this “naturalistic” solution is exposed to grave difficulties: it seems to be impossible to give an adequate account of human ends by conceiving of them merely as posited by desires or impulses. Therefore, the alternative solution has prevailed. This means that people were forced to accept a fundamental, typically modem, dualism of a nonteleological natural science and a teleological science of man. This is the position which the modern followers of Thomas Aquinas, among others, arc forced to take, a position which presupposes a break with the comprehensive view of Aristotle as well as that of Thomas Aquinas himself. The fundamental dilemma, in whose grip we are, is caused by the victory of modern natural science. An adequate solution to the problem of natural right cannot be found before this basic problem has been solved. (pp. 7-8; emphasis supplied)
The alternative that Strauss shows as opening up once the decision has already been made for a non-teleological account of nature has been made is a trivial one compared to the original decision. Even if a science of man that is in some sense “teleological” is preserved alongside a thoroughly non-teleological science of nature, the sort of freedom given to man ends up being rather different than the sort of freedom that follows from classical teleology (witness Hegel). The real problem that needs “an adequate solution” is therefore the problem of teleology in nature.
It is not entirely clear what Strauss himself thought about the issue of that basic problem. He says that he cannot deal with it adequately in Natural Right and History, in which he works (ostensibly) within the confines of “social science,” and does not address the cosmological question. His friend Jacob Klein’s profound inquiries into the significance of modern science, would, I think, have given him the tools he needed had he decided to attempt an answer to the question.
In any case, Strauss is not quite right to say that “modern followers of Thomas Aquinas” have accepted the anti-teleological conception of the heavenly bodies— not all them have. Charles De Koninck certainly did not. A contemporary thinker, deeply influenced by De Koninck, who has faced the question head on, and given a powerful argument for a teleological cosmology that takes the insights of modern science seriously is Sean Collins. I believe that his 2009 lecture, “Animals, Inertia, and the Concept of Force” (pdf, html), is one of the most important recent works of philosophy.