Aristotle, Aquinas & Emergence

I was asked to write an article relating the teaching of Aquinas to contemporary science for the journal Scientia et Fides. I decided to use and further develop the material contained in my doctoral dissertation. I expanded my reinterpretation of the classical notion of emergence, with its emphasis on the role of downward causation, in terms of the fourfold notion of causation in Aristotle and Aquinas, and the theory of divine action offered by the latter. The PDF version of the article is available HERE.

Abstract of the article:

One of the main challenges of the nonreductionist approach to complex structures and phenomena in philosophy of biology is its defense of the plausibility of the theory of emergence and downward causation. The tension between remaining faithful to the rules of physicalism and physical causal closure, while defending the novelty and distinctiveness of emergents from their basal constituents, makes the argumentation of many proponents of emergentism lacking in coherency and precision. In this article I aim at answering the suggestion of several thinkers to redefine emergence and downward causation in terms of the broader Aristotelian view of causation. In addition, I further develop this interdisciplinary conversation to include theological implications of emergentism, analyzed in reference to Aquinas’ understanding of divine action in terms of the same fourfold division of causes—bringing thus natural science, philosophy, and theology into creative and fruitful dialogue.

Keywords: emergence; downward causation; hylomorphism; teleology; Aristotle; Aquinas.



Thomism and Evolution

I’m sharing the good news. My article on the thomistic response to the theory of evolution – that I have been working on for a long time – has been published today in an online version of the coming issue of Theology and Science. you can find link to the article and a pdf of the final draft on my profile on ACADEMIA.EDU and RESEARCHGATE.NET.

The paper is significant for two reasons.

First, I’m bringing in it my discovery of a preliminary definition of natural selection in Aquinas’ commentary on Aristotle’s Physics II, 8 (198b 29-32), that can be found in In Phys. II, lect. 12, par. 253.

Second, in the theological part of the paper I bring Aquinas’ Commentary on Sentences (In I Sent., dist. 44, I, 2, co.) where Thomas — in the context of divine action in the possible perfection of the universe — says explicitly about addition of new species (multae aliae species).

Thomistic Response to the Theory of Evolution: Aquinas on Natural Selection and the Perfection of the Universe


Neither Aristotle nor Aquinas assumes the reality of the evolution of species. Their systems of thought, however, remain open to the new data, offering an essential contribution to the ongoing debate between scientific, philosophical, and theological aspects of the theory of evolution. After discussing some key issues of substance metaphysics in its encounter with the theory of evolution (hylomorphism, transformism of species, teleology, chance, the principle of proportionate causation), I present a Thomistic response to its major hypotheses. Concerning the philosophy of Aquinas I trace what might be seen as a preliminary description of natural selection in his commentary on Aristotle’s Physics. Turning toward theology, besides addressing the topics that were referred to in the past—such as: Aquinas’ reading of Genesis, his account of creation as dependence in being, secondary and instrumental causality, and univocal/equivocal predication of God—I bring into discussion Thomas’ concept of the perfection of the universe, which has been virtually unused in this context.

Key Words: Aristotle; Aquinas; Natural selection; Chance; Divine causality; Evolution; Hylomorphism; Perfection of the Universe; Teleology

Dissertation Proposal

Emergence and Divine Action:
Exploring the Dispositional View of Causation
as a New Philosophical Foundation

My dissertation proposal was accepted at the GTU systematic and philosophical theology area meeting on Oct 15. All I have to do is to have it approved by the GTU doctoral council (sometime in November) and then write it. 🙂 Few words of explanation concerning my current research that I wrote in an email sent to a scholar that I am corresponding with online, will serve as a good introduction to the topic of my work.

The reason I got interested in the dispositional metaphysics is its rejection of Humean view of causation and re-connecting with Aristotelian metaphysics and philosophy of causation. But there is not an easy connection that one can establish between the two I’m afraid. Although some thinkers like Brian Ellis argue in favor of essentialism (see his Scientific Essentialism), they are not ready, nor willing to accept hylomorphism. The other problem is teleology. Molnar speaks about the natural “physical intentionality” of powers to manifest themselves, but hardcore Aristotelians are not satisfied. For them Aristotle’s distinction between active and passive potencies is crucial. They emphasize the character of the active potencies which are causal grounds of certain effects but without being determined to those effects by nature or without requiring any stimulus condition to obtain. (See for instance the paper by Errin Clark, which will be published soon in proceedings of the ACPA conference that took place a week ago in D.C and was dedicated to dispositional metaphysics) But this whole argumentation sounds like another criticism of conditional view of causation which is criticized by several dispositionalists – so they can defend themselves here. But the question remains: how Aristotelian is dispositional metaphysics???

Complex systems approach, emergence and systems theory are fascinating in terms of their re-discovery of complex structures and their holistic approach to reality. But they are stuck with the Humean view of causation which is based on his atomistic ontology of events and his dismissal of the ontology of objects. But one ontology cannot do without the other. Objects have properties (smell, age, physical construction) which cannot be ascribed to events. But acknowledging this requires from us a step beyond efficient causation which is the only one accepted in modern science. But scientists are very suspicious about making this move and buying into formal and final causes. They want to eat the cake and have it. That is, they argue in favor of irreducible complexity in systems theory, while saying – at the same time – that after all everything is explainable at the level of physical particles. They call themselves “non-reductionist physicalists” which I think brings a logical contradiction. If they are willing to buy into formal and final causes they claim – as Deacon does – that they emerge on the way of the growing complexity of the organization of matter, whereas for Aristotle these causes are simply out there all the time and ground all structures and processes not only bottom-up or top-down, but – as my advisor Michael Dodds OP says – inside-out.

My project would be to try to propose dispositional metaphysics as a philosophical base and ontology for Deacon’s emergentism and suggest that accepting a sort of essentialism (not necessarily hylomorphic essentialism) does not contradict science but opens it to philosophy of nature which can help to overcome the causal closure imposed by modern philosophy and science. In the second part of my dissertation I will work on the theory of divine action based on emergentism. I will show that dispositional metaphysics opens the way back to the Aristotelian-Thomistic view of causation and divine action, and God/world relation, which I want to propose as an alternative to the panentheistic theology of divine action based on emergence developed by Arthur Peacocke, Philip Clayton, and Niels Gregersen.

Dominicans at the Forefront of Experimental Science

Despite several important publications (James Hannam, David C. Lindberg, and Edward Grant), the awareness of the foundations of the modern science in Middle Ages is still low among the majority of scientists. While the popular opinion sees the Renaissance thinkers (including Zabarella, Copernicus, Gilbert, Kepler and Galilei) as progenitors of a new method, it was the tension between thinkers at the medieval universities in Oxford and Paris that brought the origin of science as we know it today. Moreover, this tension between the two schools goes back to the differences between the proponents of Plato and Aristotle, which helps us to recognize and locate the actual plato-and-aristotleorigin of scientific endeavor in antiquity.

In his philosophy of nature Plato combined Pythagorean attempt to understand the cosmos and its phenomena in terms of mathematics and number with Democritus’ purely mechanical view of causation defined in terms of movements and collisions of atoms (for Plato triangle is an atomic element). Therefore, he saw mathematics as a way of arriving at the ultimate and basic reality itself, which in sensual experience is given only in ephemeral appearances. Mathematics became for him a path leading to the contemplation of eternal Ideas, which find their temporal and imperfect exemplifications in the reality accessible for us.Plato

This emphasis on mathematical component in scientific explanation was followed by medieval thinkers in Oxford. Even if the most prominent scientists among them, such as Robert Grosseteste (ca. 1168-1253) and his disciple Roger Bacon (ca. 1214-1294), said about the indispensability of experience and experiments (“in thought if not in deed”), which are supposed to verify or falsify the outcomes of physics, it is doubtful that they performed real experiments. Neither did they develop any actual method or theory of verification and falsification. They found mathematics being essential not only for understanding of all sciences, but even of the entire world in its essence. Their endeavor was supported by the nominalism of William of Ockham (ca. 1287-1347) who questioned the realism of Aristotelian common natures, claiming that terms such as quantity, motion, time, space, velocity and causality, had no other real referents than an individual substance. Although such a strong trust in theoretical and mathematical method is questionable from the contemporary point of view, we cannot forget that it was precisely this attitude that brought an important development of the philosophy of motion, which can be regarded as an origin of kinetics.

InvestigadorOn the other pole of the methodological reflection among medieval scientists we find those who did not trust mathematics as much as the empirical temper of Aristotelian tradition (rediscovered at that time at the University of Paris). They believed in man’s ability both to come to know the world of nature and to discover and name the causes of its phenomena. They regarded mathematics, as a formal and abstract discipline which applied to reality enables us to construe a subalternated type of scientific knowing, which is abstracted from empirical and sensual experience. That is why they valued more sensual experience and experiment, as well as deduction and hypothesis. Consequently, it was the academia in Paris that gave start to the reflection on dynamical problems, thus supporting the origin of a systematic science of mechanics (which – as we have seen – had its kinematic component established at Oxford).

Pivoting compass needle in a 14th-century handcopy of Peter's Epistola de magnete (1269)The experimental method and practice of the medieval science in Paris had its origins in the work of Peter Peregrinus of Maricourt (fl. 1269). His contemporary Roger Bacon was most impressed by his achievements and praised him saying that “he is a master of experiment. Through experiment he gains knowledge of natural things, medical, chemical, indeed of everything in the heavens or earth” (Opus tertium, cap. 13). Peter’s greatest contribution was naming magnet’s poles after the celestial poles, which was preceded by a series of experiments with loadstone and iron needle, carefully described in the first part of his De magnete. He also developed and employed a methodology of falsification with considerable skill in order to refute the opinion of those claiming that the loadstone derives its power from the place where it was mined. His experiments allow him to prove that the magnet gets its power from the poles of the heavens.

But the most outstanding piece of experimental work in the High Middle Ages was completed by a Dominican friar Theodoric of Freiburg (ca. 1250-1310), who studied at the University of Paris shortly after Aquinas’ death and belonged to the same German province of Teutonia as Albert the Great, being one of his successors in the provincial office. Besides a large number of opuscula in philosophy and theology – obliged by the master of the Order, Aymeric de Plaisance – he wrote his treatise “On the Rainbow and Radiant Impressions” (De iride et radialibus impressionibus), which describes his scientific experimental work. William Wallace praises the ingenuity of  his work saying that:

raindrops_rainbows_2“Theodoric’s place in the history of optics is guaranteed by his detailed analysis of the primary and secondary rainbows, of lunar and solar halos, and of other optical phenomena appearing in the earth’s atmosphere. At a time when Peter Peregrinus provided the only real precedent for experimentation, Theodoric set about systematically investigating the paths of light rays that generate radiant colors in the earth’s atmosphere, and did so largely by experimental means. He utilized spherical flasks filled with water, crystalline spheres, and prisms of various shapes to trace the refractions and reflections involved in the production of radiant colors. He also worked out a theory of elements that was related to his search for optical principles, and which stimulated experimentation along lines that could more properly be called verification than anything we have seen thus far. (…) He thus has been hailed as a precursor of modern science and his work read as though he were using mathematical and experimental techniques developed only in the seventeenth century” (Causation and Scientific Explanation, Vol. 1).

The core of the originality and novelty of his method consists in the fact, that Theodoric did not only observe the way in which rainbows are produced in nature (experience), but also attempted to duplicate the process under controlled laboratory conditions, where he could observe all component factors in detail (experiment). While those searching for the material cause of a rainbow saw it in a raincloud (they treated a spherical flask filled with water as a miniature of a cloud), Theodoric saw a globe of water in laboratory setting as a magnified raindrop. This observation helped him to understand that the entire rainbow is an aggregate of partial spectra produced by individual drops.

531454824_215Wallace notices that Theodoric mentions the term experiment (experimentum) at least 12 times in De iride. He develops a deliberate empirical procedure, at times involving measurement, in order to verify or falsify a proposed explanation. It is hard not to see in his methodology a direct link to the hypothetical-deductive method of modern and contemporary science. What is most important from my perspective (following Wallace), is the fact that Theodoric does all this in the context of an underlying Aristotelian methodology, concentrated on the search for four causes of the rainbow (even if he concentrates on material and efficient causes, more than on formal and final). This attitude is based on an underlying metaphysical realism, which searches for causes in the real, physical world, rather than in the mathematical sphere, which naturally cannot be neglected.

The whole story shows an important interplay between the two radically different approaches to reality and scientific method in Oxford and Paris. Not without tensions, this dispute gave birth to modern science, and it gives me a great joy that I find a Dominican friar among its precursors.

William Wallace, Causality and Scientific Explanation, Vol. 1
James Hannam, God’s Philosophers: How the Medieval World Laid the Foundations of Modern Science