The originally British mathematician and philosopher Alfred North Whitehead (1861–1947) was profoundly concerned with the inter-relatedness of things. His later “philosophy of organism” inspired a movement of so-called “process theology”.

Whitehead was one of the inventors of universal algebra, which extends algebraic principles to symbolic representations of things that are not numbers. He collaborated with Bertrand Russell on the famous Principia Mathematica (1910, 1912, 1913) , which sought to ground all of mathematics in the new mathematical logic, but was less attached than Russell to the goal of reducing math to logic.

He did work in electrodynamics and the theory of relativity, emphasizing a holistic approach and the nonlocal character of electromagnetic phenomena. Counter to the spirit of the time, he developed a philosophy of science that aimed to be faithful to our intuitions of the interconnectedness of nature. He characterized mathematics as the abstract study of patterns of connectedness. In Science and the Modern World (1926), rejecting the world views of Newton and Hume as understood by the logical empiricists, he developed alternatives to then-dominant atomistic causal reductionism and sensationalist empiricism. Eventually, he turned to what he and others called metaphysics.

His Process and Reality (1929) is a highly technical work that is full of interesting insights and remarks. It aims to present a logically coherent system that radicalizes the work of John Locke in particular, but also that of Descartes, Spinoza, and Leibniz. As with many systematic works, however, it doesn’t engage in depth with the work of other philosophers.

Whitehead’s radicalization involves, among other things, a systematic rejection of mind-body dualism; of representationalism; of metaphysical applications of the subject-predicate distinction; and of Locke’s distinction between “primary” (mathematical) and “secondary” (nonmathematical) qualities. Plato and Aristotle both get positive mention. Whitehead thoroughly repudiates the sensationalist direction in which Hume took Locke’s work; aims deliberately to be “pre-Kantian”; and seems to utterly ignore Hegel, though he gives positive mention to the “absolute idealist” F. H. Bradley.

He wants to promote a thoroughgoing causal realism and to avoid any subjectivism, while eventually taking subjective factors into account. He wants to reinterpret “stubborn fact” on a coherentist basis. He is impressed by the work of Bergson, and of the pragmatists William James and John Dewey.

For Whitehead, “experience” encompasses everything, but he gives this an unusual meaning. Experience need not involve consciousness, sensation, or thought. He stresses the realist side of Locke, and wants to apply some of Locke’s analysis of the combination of ideas to realities in general.

He says that the world consists fundamentally of “actual entities” or “actual occasions” or “concrescences”, which he compares to Descartes’ extended substances. However, he interprets Einstein’s theory of relativity as implying that substances mutually contain one another, a bit like the monads in Leibniz.

For Whitehead, every actual entity has a kind of self-determination, which is intended to explain both human freedom and quantum indeterminacy. On the other hand, he also says God is the source of novelty in the universe. Whitehead recognizes what he calls eternal objects, which he compares to Platonic ideas, and identifies with potentiality.

Compared to the Aristotelian notions of actuality and potentiality I have been developing here, his use of actuality and potentiality seems rather thin. Actuality is just factuality viewed in terms of the connections of things, and potentiality consisting in eternal objects amounts to a kind of abstract possibility. His notion of causality seems to be a relatively standard modern efficient causality, modified only by his emphasis on connections between things and his idea of the self-determination of actual entities. His philosophy of science aims to be value-free, although he allows a place for values in his metaphysics.

According to Whitehead, perception has two distinct modes — that of presentational immediacy, and that of causal efficacy. Humean sensationalism, as codified by early 20th century theories of “sense data”, tries to reduce everything to presentational immediacy, but it is our intuitions of causal efficacy that connect things together into the medium-sized wholes recognized by common sense. As far as it goes, I can only applaud this move away from presentational immediacy, though I have also tried to read Hume in a less reductionist way. (I also want to go further, beyond intuitions of efficient causality in the modern sense, to questions of the constitution of meaning and value that I think are more general.)

In his later works, he emphasizes a more comprehensive notion of feeling, which he sees as grounded in subjective valuations, glossed as having to do with how we take various eternal objects. Compared to the logical empiricism that dominated at the time, this is intriguing, but I want to take the more radically Aristotelian (and, I would argue, also Kantian) view that values or ends (which are themselves subjects of inquiry, not simply given) also ultimately drive the constitution of things we call objective. I also don’t see “metaphysics” as a separate domain that would support the consideration of values, over and above a “science” that would ostensibly be value-free.

Whitehead considered the scientific reductionism of his day to exemplify what he called the “fallacy of misplaced concreteness”. What I think he wanted to question by this was the idea that scientific abstractions are more real or more true than common-sense apprehensions of concrete things. I would phrase it a bit differently, but the outcome is the same. Abstractions can have great interpretive value, but they are things entirely produced by us that have value because they help us understand concrete things that are more independent of us.

Attempting to take into account the idea from quantum mechanics that reality is not only relational but also granular, he made what is to me the peculiar statement that “the ultimate metaphysical truth is atomism”. Whitehead is certainly not alone in this kind of usage; indeed, the standard modern physical notion of “atoms” allows them to have parts and internal structure. That concept is fine in itself, but “atom” is a terrible name for it, because “atom” literally means “without parts”. The word “atom” ought to denote something analogous to a point in geometry, lacking any internal features or properties whatsoever.

Be that as it may, Whitehead sees an analogy between the granularity of events in quantum mechanics and the “stream of consciousness” analyzed by William James. “Your acquaintance with reality grows literally by buds or drops of perception. Intellectually and on reflection you can divide these into components, but as immediately given, they come totally or not at all” (Process and Reality, p. 68). To me, this is an expression not of atomism but of a kind of irreducibility of medium-sized things.

Anyway, Whitehead’s “atomic” things are events. Larger events are composed of smaller events, but he wants to say there is such a thing as a minimal event, which still may have internal complexity, and to identify this with his notion of actual occasion or actual entity.

I like the identification of “entities” with occasions. For Whitehead, these are a sort of what I call “medium-sized” chunks of extension in space-time. Whitehead’s minimal events are nonpunctual.

Freed of its scholastic rigidifications, this is close to what the Aristotelian notion of “primary substance” was supposed to be. I think of the latter as a handle for a bundle of adverbial characterizations that has a kind of persistence — or better, resilience — in the face of change. Only as a bundle does it have this kind of resilience.

Although — consistent with the kind of grounding in scientific realism he is still aiming at — Whitehead emphasizes the extensional character of actual occasions, they implicitly incorporate a good deal of intensional (i.e., meaning-oriented, as distinguished from mathematical-physical) character as well. Following Brandom’s reading of Kant on the primacy of practical reason, I think it is better to explain extensional properties in terms of intensional ones, rather than vice versa. But I fully agree with Whitehead that “how an actual entity becomes constitutes what that actual entity is” (p. 23, emphasis in original), and I think Aristotle and Hegel would, too.

According to the Stanford Encyclopedia of Philosophy, Whitehead’s work was attractive to theologians especially because it offered an alternative to the traditional notion of an omnipotent God creating everything from nothing. Whitehead argued that the Christian Gospel emphasizes the “tenderness” of God, rather than dominion and power: “not… the ruling Caesar, or the ruthless moralist, or the unmoved mover. It dwells upon the tender elements in the world, which slowly and in quietness operate by love” (p. 343). “The purpose of God is the attainment of value in the world” (Whitehead, Religion in the Making, p. 100). God for Whitehead is a gentle persuader, not a ruler.

(I would not put unmoved moving in anywhere near the same bucket as ruling omnipotence. Unmoved moving in Aristotle is attraction or inspiration by a pure end, where all the motion occurs in the moved thing. It is not some kind of ruling force that drives things.)