Mechanical Metaphors

Perhaps the greatest contribution of the Italian physicist, astronomer, and engineer Galileo Galilei (1564-1642) — regarded by many as the single most important originator of modern, mathematically oriented natural science — was a unified explanation of both astronomical and earthly phenomena by the same set of mathematical principles for analysis of the behavior of physical bodies and matter. This was a generalized mechanics of solid bodies.

The tremendous power of this new way of understanding the physical behavior of bodies is undeniable. At least until the computer age, it has been the main basis of modern engineering and technology.

A historical side effect of this immensely successful development has been the promotion of solid-body mechanics as a kind of privileged metaphor for causality in general. I’ve several times discussed the transformation of Aristotle’s notion of efficient cause (most fundamentally, the means to actualization of an end) into the very different notion of “driving” cause or “motor” by medieval and early modern authors (see Efficient Cause, Again; Su├írez on Agents and Action; Effective vs “Driving”; Not Power and Action). In combination with a very un-Aristotelian tendency to reduce other causes to efficient causes, this created a ripe condition for the spread of a view of causality in general in terms of metaphors based on solid-body mechanics. We are now so used to this that it takes effort to imagine any other view.

But the solid-body interaction metaphor ultimately leads to an impoverished, overly narrow view of causality in general. (For an alternative, see Aristotelian Causes.) Even within mechanics proper, solid bodies are no longer the paradigmatic, privileged case. At scales that are too small or too large, analogies to the behavior of medium-sized solid bodies break down. In broader contexts, wave phenomena are as important as the analysis of solid bodies. The great Roman poet-physicist Lucretius already had the insight that in the general case, atoms in aggregate behave more like liquids than like solids.

Irreducible to any purely mechanical paradigm, disciplines like earth sciences, ecology, medicine, economics, and computer science provide many examples of more complex and subtle interactions and structures that suggest a new need for something more like an Aristotelian view of causality, as having more to do with forms of things than with force.

Aristotelian Subjectivity Revisited

My previous article on this was a bit narrow, focused only on an Aristotelian analogue for the sort of “transcendental” subjectivity developed by Kant and Hegel. Of course, the whole field of “subjectivity” is much broader than that, and properly transcendental subjectivity has little to do with the empirical subjectivity that we have in mind when we call something “subjective”. Here I’d like to begin to round out the picture. (In the background, I’m also imagining what Aristotle might say in response to Hegel’s Phenomenology.)

It is in fact something of a truism that none of the Greeks had a modern concept of the human “subject”. The closest (still distant) analogue is what gets conventionally translated by the etymologically related term “substance” in Aristotle. The elementary notion of substance as a literally existing logical/syntactic substrate for properties –“something underlying something else” — from the Categories was influentially referred to by Heidegger as “subjectity” (intended to stand in constrast to “subjectivity“).

The explanatory role of a literal notion of substrate is raised again in the Metaphysics. Aristotle says the most obvious candidate for a substrate of things is matter. But then he goes on to deconstruct and ultimately discard the whole notion that the most important kind of explanation of things involves reference to a literal substrate. Form — identified with essence or definition, and “what it was to have been” a thing — is then developed as providing more fundamental explanation than any substrate; then form itself is given a deeper explanation in terms of actuality and potentiality.

But neither the elementary account of “something underlying” in the Categories nor the sophisticated discussion in the Metaphysics makes any reference at all to the sentience and agency that are equally fundamental to modern notions of a human “subject”.

Separate from all of this, Aristotle identifies humans as those animals that have language and the ability to reason, which he considers as depending on language. I have argued that the main resource for an implicit notion of transcendental subjectivity in Aristotle is actually his ethical writings. The treatise on the “soul” (psyche) deals with bodily growth, nutrition, movement, and reproduction; with sense perception and imagination; and also with thought, which he refers to as coming to the soul “from outside”. Related treatises address memory and dreams. Human emotions, on the other hand, he deals with not in the “psychological” treatises but rather in the Rhetoric. The context in which Aristotle treats emotion is thus social and communicative rather than inward-looking. He also treats a kind of emotional maturity as a prerequisite for ethical development. He has a refined and well-differentiated notion of situated agency and ethical responsibility, but lacks the obsession with identity shown by many later authors.

I want to suggest that the “whatness” of subjectivity-forms — whether empirical or transcendental — is far more interesting and practically relevant than the supposed abstract “existence” of subject or substrate entities. This is true regardless of whether we are dealing with empirical or transcendental subjectivity. In Heideggerian terms, I want to decouple subjectivity from presumptions of subjectity.

As regards the Aristotelian soul, in Naissance du Sujet (volume 1 of Archeologie du Sujet), Alain de Libera lists four recent analytic interpretations: 1) the psyche is identical to the body; 2) the psyche is an attribute of the body; 3) the body “constitutes” the psyche; 4) the psyche is an immaterial substance. Actually, none of these seems to me to adequately capture Aristotle’s hylomorphism, or notion of the complementarity of “form” and “matter” (neither of which individually means quite what it might seem to, either — see above links). I am also sympathetic to the reading that Aristotelian matter is a relative concept, so that something could be the material for something else that is in turn material for another thing. Something similar, I think, could be said of form.

The relation of soul to body is clearly presented as an instance of the relation of form to matter, though it seems that the relation of form to matter may be different in different cases. In any case I do not think the form/matter relation is intended as an instance of the substance/accident relation. (The notion of “substantial form” was an original development of the Latin medieval tradition, not found in Aristotle, and the bits I understand of the medieval debate on unity or multiplicity of substantial forms further complicate the picture. The key to this whole territory is to understand that there are very many highly distinct and sophisticated positions in the tradition on issues of this sort.)

A further complication involves the relation between “soul” and the “intellect” that “comes from without”, which has a long and fascinating history in the commentary tradition, extending from Alexander of Aphrodisias through the Arabic tradition to the Latin tradition of Albert the Great.

The great Arabic commentator Averroes was apparently the first to ask what is the “subject”, in the substrate sense, of human thought. He came up with the novel suggestion that individual human thought has two such “subjects”: one belonging to the soul that is involved with the body and perception, and one that is an immaterial source of concepts, belongs to the whole human community, gains content over time, and would cease to exist if there were no more humans.

Another intriguing complication in the historical Western tradition is the clear stance taken by Augustine that human mind, soul, or spirit should definitely not be taken as a subject in the substrate sense, e.g., for knowledge or love.

Matter, Mind

I don’t think any kind of stuff could come first, be it matter or some sort of mind-stuff. What comes first in the sense of principle would be something like form or structure or mediation. (“First” in the general sense of principle is said in several ways, but I’m inclined to re-collapse some of them. These days, I consider ontology to be mostly either redundant with semantic and epistemological methodological senses, or else just a mistake. This leaves a long view of methodology as the best candidate for a principle.) The air of paradox associated with saying something like mediation comes first is dispelled if we recall that apparent immediacy is mediated immediacy. This just reflects the fact that methodologically, we are never at a completely pure beginning, and always start in medias res.

Mind especially seems to me not best approached as a kind of stuff at all. It is first and foremost a way of doing. (See also Mind Without Mentalism.) Then, too, what is loosely called the “matter” that we care about in concrete cases often comes down to potentiality, or dispositions to respond in certain ways when acted upon (which is distinct from Aristotelian matter, as I understand it). Both of these are adverbial characterizations, though things of this sort can always be nominalized for convenient reference.

Aristotle suggests that what is first “for us” (the short view of methodology) is some sort of activity that we tentatively pick out within appearance. We then move forward by developing the adverbial characterization of that activity in terms of form or structure or mediation. (See also Objectivity of Objects; First Principles Come Last; Owl; Passive Synthesis, Active Sense; Radical Empiricism?; Realism, Idealism; Johnston’s Pippin.)

Matter, Potentiality

I’ve suggested nonstandard readings of both Aristotelian matter and Aristotelian potentiality. While traditionally there is thought to be a loose analogy such that matter is to form as potentiality is to actuality, the two concepts as I am reading them are sharply distinct. Matter captures the accumulation of contingent fact. Potentiality captures counterfactually robust inference. Matter particularizes, while potentiality universalizes.

Potentiality seems to me to be a kind of form. This is a bit tricky, because an important classical sense of Aristotelian matter that I have not been emphasizing is associated with a disposition to respond in certain ways when acted upon. This, however, sounds like counterfactual potentiality to me.

Aristotelian Matter

Aristotelian “matter” and “material cause” mainly capture notions of circumstance, contingent fact, mediation, and what some 20th century writers called sedimentation.

Early Greek mathematics was not sufficiently advanced to be of much help in understanding natural processes, so Aristotle instead pioneered a logical/semantic approach to our experience of sensible nature. In accordance with this, “matter” for Aristotle is what Brandom would call an expressive metaconcept, rather than being a theory-laden empirical concept like the modern notion. We need to be careful moving between the two.

For Aristotle, matter is not a subsisting thing but a relative concept that has an expressive role. “Matter” and “form” are correlatives, only analytically distinguishable, though the relation is not quite symmetrical (form seems to be more primary). All physical things are conventionally referred to as “composites” of the two, but this should not be taken to mean that either has independent existence. (See also Hylomorphism.)

The relation between matter and form is loosely but definitely not strictly analogous to that between potentiality and actuality. Matter gives concrete embodiment to particulars, whereas potentiality is what provides the space for construction of universals.

Unlike Descartes, Aristotle does not associate matter in any direct way with mathematically analyzable extension. One of his usages for “matter” is as the inferred substrate for sensible properties. But alongside this, a different account is actually more prominent. Some “form” or way of being and doing makes the composite the particular kind of thing it is. In this context, “matter” ends up comprising the concrete circumstances of the actual functioning of a way of being and doing.

Modern people are used to thinking of form as a predicate of some matter. Some in the ancient world thought this way, too, but Aristotle prefers to speak in the opposite way, and to predicate the matter of the form.

Aristotelian matter refers to circumstance, to a body of what is the case about some particular actualized form, more primarily than to a body of stuff. What is of interest with matter is particular matters, or “a” matter, or “the” matter of some particular form — the circumstances of its actualization.

The Greek commentator Alexander of Aphrodisias postulated an ultimate “prime matter” that was distinguished by having no properties at all, which by implication would put all properties whatsoever on the side of form. At the other end of the spectrum, some later commentators spoke of a “proximate matter” (i.e., the matter closest to the form) as highly structured, and as including things like the body of an animal.

Aristotle’s various usages, if reified, would result in a layering of form/matter distinctions. (In the middle ages, there was heated debate over the so-called “unity or plurality of substantial forms”. Theologians were much concerned over the relation of soul to body. Albert the Great, Thomas Aquinas and others took seriously Aristotle’s description of soul as the “form of the body”. Augustinians wanted a dualistic separation of soul and body, more like the pilot in the ship that Aristotle rejected. They therefore argued that the body already had a form of its own, and that the form of the soul is superimposed on it (a “plurality of substantial forms”). The notion of “substantial form” was a late refinement intended to be strictly univocal, where Aristotle’s general usage of “form” had instead been self-consciously overdetermined, overflowing any such conditions in the course of its dialectical development.)

Aristotelian matter is implicitly not just immediate circumstance, but always a result of a sort of layering or accumulation of circumstances over time, including some feedback loops. This is important for the kind of generalization we should expect from Aristotelian science.

Cartesian extensionality is perfectly homogeneous. Aristotelian matter is anything but that. It is a site of differences (as form is also, in a complementary way). The virtual layering or accumulation I have spoken of is a very weak kind of unity. Aristotle’s notions of necessity and universality are also both deliberately weak notions. Something is said to be “necessary” just if there is no known counter-instance. “Universal” means “said of many things”, not “said unconditionally”.

Aristotelian “science” does not aim to codify laws in the modern, univocal sense. It is an open hermeneutic that seeks to understand processes in terms of patterns, while recognizing inherent contingency in matters of fact. Particularly in the biological works, there is a genealogical intertwining of form and accident that makes it impossible to strictly separate the two. Aristotelian natural teleology is not only purely immanent, but also never univocal, as this intertwining makes clear. It gives us tendencies only, never strict predetermination.