- From Aristotle to John Searle and Back Again:Formal Causes, Teleology, and Computation in Nature
Talk of information, algorithms, software, and other computational notions is commonplace in the work of contemporary philosophers, cognitive scientists, biologists, and physicists. These notions are regarded as essential to the description and explanation of physical, biological, and psychological phenomena. Yet, a powerful objection has been raised by John Searle, who argues that computational features are observer-relative, rather than intrinsic to natural processes. If Searle is right, then computation is not a natural kind, but rather a kind of human artifact, and is therefore unavailable for purposes of scientific explanation.
In this paper, I argue that Searle’s objection has not been, and cannot be, successfully rebutted by his naturalist critics. I also argue, however, that computational descriptions do indeed track what Daniel Dennett calls “real patterns” in nature. The way to resolve this aporia is to see that the computational notions are essentially a recapitulation of the Aristotelian-Scholastic notions of formal and final causality, purportedly banished from modern science by the “mechanical philosophy” of Galileo, Descartes, Boyle, and Newton. Given this “mechanical” conception of nature, Searle’s critique of computationalism is unanswerable. If there is truth in computational approaches, then this can be made sense of, and Searle’s objection rebutted, but only if we return to a broadly Aristotelian-Scholastic philosophy of nature. [End Page 459]
The plan of the paper is as follows. The next section (“From Scholasticism to Mechanism”) provides a brief account of the relevant Aristotelian notions and of their purported supersession in the early modern period. The third section (“The Computational Paradigm”) surveys the role computational notions play in contemporary philosophy, cognitive science, and natural science. The following section (“Searle’s Critique”) offers an exposition and qualified defense of Searle’s objection to treating computation as an intrinsic feature of the physical world—an objection that, it should be noted at the outset, is independent of and more fundamental than his famous “Chinese Room” argument. In the fifth section (“Aristotle’s Revenge”), I argue that the computational paradigm at issue essentially recapitulates certain key Aristotelian-Scholastic notions commonly assumed to have been long ago refuted and that a return to an Aristotelian philosophy of nature is the only way for the computationalist to rebut Searle’s critique. Finally, in “Theological Implications,” I explore ways in which computationalism, understood in Aristotelian terms, provides conceptual common ground between natural science, philosophy, and theology.
From Scholasticism to Mechanism
Scholastic thinkers, building on Aristotle, developed a complex network of interrelated concepts they regarded as essential to understanding the natural order. These include the distinctions between actuality and potentiality, substance and accidents, substantial form and prime matter, efficient and final causes, and so on. Contrary to a very common misconception, these notions are not in competition with scientific explanations as we now understand the notion of a scientific explanation. Rather, they are part of a metaphysical framework that, the Scholastic maintains, any possible scientific explanation must presuppose, and in light of which the results of scientific investigation must be interpreted.
I happen to think this framework is correct, and I have presented a thorough exposition and defense of it in my book Scholastic Metaphysics.1 For present purposes, three Aristotelian-Scholastic notions are especially important: substantial form, immanent teleology, and proportionate causality. Let’s consider each one in turn. A “substantial form” [End Page 460] is contrasted with an “accidental form,” and the difference can be illustrated with a simple example. Consider a liana vine, which is the sort of vine Tarzan uses to swing around the jungle. Like any natural object, a liana vine has certain characteristic properties and operations. It takes in water and nutrients from the soil through its roots, exhibits distinctive growth patterns, and so forth. Suppose Tarzan makes a hammock using several living liana vines. The resulting object will also have certain distinctive features, such as being strong enough to support a grown man, being comfortable enough to take a nap in, and so on.
Now there is a clear difference between these two sets of features. The tendencies to take in water and...