Neo-Aristotelianism is indeed resurgent in contemporary philosophy. The renaissance has been underway for at least fifty years, beginning with a new focus on classical metaphysical themes by Roderick Chisholm, David M. Armstrong, Alvin Plantinga, and Robert M. Adams. In the 1960’s and 70’s, these anglophone philosophers began digging themselves out of the rubble of logical positivism, which had declared nearly every question addressed by Plato and Aristotle to be “nonsensical.”

Tracing the Movement

The development of modal logic, the logic of necessity, possibility, and contingency, by C. I. Lewis, Rudolf Carnap, Saul Kripke, Ruth Barcan Marcus, and Arthur Prior in mid-century was an essential first step. Aristotle’s greatest discovery may have been the actual/potential distinction, which was universally rejected by early twentieth-century philosophers, like Bertrand Russell, Ludwig Wittgenstein, W. V. O. Quine, and the Vienna Circle. Modal logicians demonstrated that a coherent semantics and logic for the different modalities could be constructed.

A second crucial step in the process was the resuscitation of the notion of causation, which Bertrand Russell had dismissed in 1914 as a useless relic. G. E. M. (Elizabeth) Anscombe’s inaugural lecture at Cambridge in 1971, “Causality and Determination,” was a watershed event, followed closely by J. L. Mackie’s The Cement of the Universe (1974) and Rom Harré and E. H. Madden’s Causal Powers (1975). Michael Tooley (1993) contributed significantly to the case for causal realism. Interest in causal powers and dispositions accelerated at the end of the twentieth century and the beginning of the twenty-first, with pioneering work by C. B. Martin (who engaged in a crucial debate on dispositions with David Armstrong and U. T. Place in 1998), Alexander Bird (1998), Stephen Mumford (1998), Brian Ellis (1991 and 2001), myself (Realism Regained, 2000), and George Molnar (Causal Powers, 2003).

The strange new respect given to causation in the latter half of the twentieth century arose from important new insights drawn from the philosophy of language and epistemology. Edmund Gettier, in one of the most influential articles of the century, “Is Justified True Belief Knowledge?” (1963), posed a puzzle about the nature of knowledge that led to the recognition that a causal connection between the world and the sensory experience and memory of the observer is indispensable. Parallel investigations in the philosophy of language in the 1970’s by Keith Donnellan, Saul Kripke, and Gareth Evans revealed that the semantic connections between words and their meaning also rely on chains of causal connection.

Next, Kit Fine liberated the theory of modality from its dependence on Leibniz’s abstract possible worlds and brought Aristotelian essence back to fore in an important article in 1994 (“Essence and Modality”), building on crucial work by Saul Kripke (Naming and Necessity, 1980) and David Wiggins (Sameness and Substance, 1980). What must happen and what can happen is ultimately determined by the intrinsic natures of things, i.e., their essences, what it-is-to-be a thing of that sort.

Nancy Cartwright’s work on the philosophy of science, beginning with her influential How the Laws of Physics Lie (1983), built on the new foundations of causal realism, further liberating philosophy from the obsession with passively observed regularities that had resulted from David Hume’s anti-Aristotelian philosophy. Cartwright described how experimental scientists isolate and interact with the systems they are studying, so as to manifest the intrinsic powers they possess. Cartwright’s work also demonstrated that the notion of causation, even if it doesn’t appear in our most “fundamental” theories of particles and gravity, is indispensable in all of the so-called special sciences, like chemistry, astronomy, and the social sciences. Brian Ellis, Alexander Bird, Stephen Mumford, and Rani Lill Anjum built on the Cartwrightian foundation, creating a fresh appropriation of Aristotle in contemporary philosophy of science. In 2018, William Simpson, Nicholas Teh, and I edited Neo-Aristotelian Perspectives on Contemporary Science, gathering work that applies this new approach to quantum physics, biology, and the social and human sciences.

Another stream that led to the Aristotelian revival centered on issues of ontology (what there is). Quine rehabilitated the subject with his essays in the 1940’s, and Roderick Chisholm’s work on the work of Austrian philosopher Franz Brentano (1838–1917) proved a crucial link between the late scholastic Aristotelianism of Brentano’s metaphysics and contemporary analytic philosophy.Here again, Elizabeth Anscombe was a pioneer, whose masterful “Modern Moral Philosophy” issued in 1958 a radical challenge to the entire scope of analytic moral philosophy in her day. Peter van Inwagen defended an explicitly Aristotelian answer (centered on living organisms) to the question of the ontology of the material world in Material Beings (1990), which spurred other developments in the direction of even greater Aristotelian orthodoxy by philosophers like David Oderberg, Anna Marmodoro, Michael Rea, Kathrin Koslicki, and William Jaworski. Variations on Aristotle’s “hylomorphism” (which sees material things as compounds of ‘form’ and ‘matter’) have been proposed by E. J. Lowe, Mark Johnston, and Kit Fine.

At the same time, a comparable revolution in ethics and value theory was taking place. Here again, Elizabeth Anscombe was a pioneer, whose masterful “Modern Moral Philosophy” issued in 1958 a radical challenge to the entire scope of analytic moral philosophy in her day, whether utilitarian, Kantian, or intuitionist. Anscombe’s bombshell triggered the development of the virtue ethics tradition, created by Alasdair MacIntyre (After Virtue, 1984), Philippa Foot (Virtues and Vices, 1979), Julia Annas (1994), John McDowell (Mind and World 1994), Linda Zagzebski, and Rosalind Hursthouse (1999), all of which built upon Aristotle’s virtue-based theory in The Nicomachean Ethics. Most (although not all) of virtue ethics is explicitly Aristotelian in inspiration, with Aristotle’s conception of happiness (eudaemonia) coming into renewed attention, with its foundation in the teleology of human nature—especially in work by Foot (Moral Goodness), MacIntyre (Dependent Rational Animals), and Michael Thompson.

Of course, scholars of Aristotle and the Aristotelian tradition have played an essential role, especially those who were most familiar with issues in contemporary philosophy, such as Jonathan Lear, David Charles, Miles Burnyeat, Montgomery Furth, Theodore Scaltsas, Sarah Broadie, Frank A. Lewis, and Jonathan Barnes. Scholars of Aristotelian scholasticism were also critical, including Peter Geach, Norman Kretzmann, Eleonore Stump, Marilyn M. Adams, Calvin Normore, and Guya Klima. These scholars revealed the great debt that modern science owes to Aristotle and scholasticism and debunked many of the myths about the supposedly dogmatic and rigid tenor of Aristotle’s system.

Finally, I should mention the central and ironic role that David Lewis’s philosophy has played. Lewis was probably the best and most influential philosopher working in the areas of metaphysics and philosophy of mind in the twentieth century. He was decidedly not Aristotelian, in temperament or doctrine. Instead, he brought inspiration from the minimalist and skeptical philosophy of David Hume to his task.Lewis was probably the best and most influential philosopher working in the areas of metaphysics and philosophy of mind in the twentieth century. This was already ironic, since Hume is famous for insisting that all the works of “school metaphysics” be consigned to the flames, and Hume would certainly have included Lewis’s extra-scientific speculations about the constitution of the world in this conflagration. Lewis’s prodigious creativity was primarily devoted to creating a thoroughly anti-Aristotelian conception of ontology, powers, causation, and potentiality. Through his acuity and clarity, both the advantages and defects of the alternative became clear to all. As time passes, the striking defects of Lewis’s Neo-Humeanism have been most persuasive, adding great impetus to the Aristotelian counter-movement. These defects include: the reification of mere possibilities as concrete parallel universes, the denial that any power or disposition is intrinsic to its bearer, the inability to explain the arrow of time, the inability to make sense of objective probability, the extreme anthropocentricity and even ethnocentricity of Lewis’s account of natural laws, the Neo-Humean’s reversal of the order of explanation between laws and their instances, and the strong support that the Neo-Humean account gives to radical inductive skepticism (e.g., skepticism about the future and other unobserved events). Tim Pickavance and I develop these and similar objections in The Fundamentals of Metaphysics (Wiley-Blackwell, 2017). I am not claiming that analytic philosophy has reached a consensus on these matters: the temptation to reduce reality to our own abilities to verify it (what we might call the “Protagoran” temptation, after the ancient Sophist Protagoras, who stated that “Man is the measure of all things”) will always have it attractions. However, the alternative metaphysical realism of Aristotle, which recognizes the existence of a reality that always lies in part beyond the limits of our knowledge, has gain renewed vigor. For Neo-Aristotelians, the arrow of time is no problem, since time is merely the measure of change, and change is the result of the actualization of a causal power, which has an intrinsic directionality from condition to manifestation. Laws are objective and explain their instances, because the true laws of nature encode general facts about causal powers that manifest themselves in each particular case. Inductive skepticism poses no threat, because Aristotelians do not concede to the skeptic the real possibility of chaotic, counter-inductive scenarios.

In the realm of science, the quantum revolution which occurred 100 years ago was in fact an Aristotelian counter-revolution, as was recognized at the time by Werner Heisenberg (Physics and Philosophy, 1958). Quantum physics destroys the atomistic materialism that had dominated science for 300 years, revealing that so-called “particles” are not tiny, individual packets of matter but rather dispersed and interconnected waves of potentiality. Quantum theory is resolutely holistic and top-down in nature, enabling us to recognize the causally fundamental status of macroscopic systems, including living organisms. Quantum microphysics is explicitly self-limiting: it makes sense only in relation to a separate world or domain of observers and their macroscopic instruments, since it describes, not the location of microscopic entities, but only the probabilities of certain macroscopic events. The threat to human agency of physical reductionism and determinism has thus disappeared. Even teleology, the Aristotelian doctrine that natural things move spontaneously toward their proper ends, has been restored in the form of the least action principle (as in Richard Feynman’s path integral formulation). Systems move naturally along the best (most economical) path.

Aristotle and the Evangelization of the West

Why does any of this matter to Christians? We know from historical experience that a culture shaped by Aristotle’s philosophy is exceptionally receptive to the gospel. Just as Roman law, Roman roads, and the freedom of the seas under the Roman Empire were key elements in the rapid spread of the gospel in late antiquity, Roman culture provided an intellectual environment primed for the implantation of Christian ideas, having absorbed the central tenets of Aristotle’s philosophy through the thought of later Stoics, Cicero, and the Neo-Platonists.Why does any of this matter to Christians? We know from historical experience that a culture shaped by Aristotle’s philosophy is exceptionally receptive to the gospel. Aristotelian Neo-Platonism in Alexandria brought both pagans and Christians together in fruitful collaboration. Eventually, pagan Aristotelians saw Christianity as the greatest threat, precisely because there was so much common ground between them. Aristotelians recognized the existence of objective moral standards, anchored in human nature and shared by all human beings. They believed in a transcendent, intelligent cause of the existence of the cosmos, and they believed that there is a divine spark of reason within human beings, enabling us to understand God’s creation to a significant degree. They gave central importance to the contemplation of these eternal truths, and they instructed their students to find their highest good in cooperation with others in a just society.

The principal cultural obstacles to the gospel in the world today arise from the absence of the salutary influence of Aristotle. The modern obsession with human technology and the mastery over nature and the post-modern despair about the existence of truth and transcendent meaning are both symptoms of the displacement of Aristotle by Francis Bacon’s technocratic pragmatism in the seventeenth century and Jean-Jacques Rousseau’s sentimental egoism in the eighteenth. As the Neo-Aristotelian revival gains strength, we may hope to see a new era of fruitfulness for evangelization of the Western world.