One of the great strengths of Aristotle’s approach to things is the way it makes use of multiple, complementary kinds of explanation. The paired modalities of actuality and potentiality and the four “causes” (ends and means, form and materiality) all interweave together to create rich tapestries of understanding. Aristotle famously said that to know is to be able to explain, and his notion of explanation is clearly hermeneutic and expansive, rather than reductive. (See also Interpretation; What and Why.; Difference; Classification; Definition.)
I think modern philosophy generally is handicapped in its thinking about the empirical world by its lack of a notion like Aristotelian potentiality. To build context, I need to first say a bit more about the role of actuality.
The modern concept of a factual, existing world is relatively close to Aristotelian actuality, but the first big difference is that it is not paired with anything. The modern concept of a factual world is something that is supposed to be complete in itself, whereas for Aristotle, actuality in the world is always complemented by some correlative potentiality. Aristotle did not consider actuality alone to be sufficient to account for the world as we experience it.
Actuality also does not exactly correspond to a state of things, but rather expresses what is effectively operative. This is semantically a bit deeper than a notion of state. At the same time, it does not have state’s strong implications of complete determination. It also does not have the monolithic unity of a state. Actuality in the world consists of many coexisting things. Further, it is not intended by itself to provide all the resources needed to account for change and what happens next. This is related to the fact that for Aristotle, the operative determination of things is not entirely univocal. (See also Equivocal Determination.)
Enter potentiality. Potentiality is exactly what is not univocal in the actual determination of things. It corresponds to multiple alternative concrete possibilities of realization already implicit in current reality. This is a far more specific notion than mere logical possibility. Potentiality is closely tied to and informed by the current actuality, in that it exactly occupies the real gaps or holes in the actuality’s incompletely univocal determination. For each aspect of things where there is not univocal determination, there are instead multiple potential alternatives. This correlates with the fact that, for Aristotle — in contrast to Poincaré’s classic formulation of modern determinism — the present does not completely determine the future.
Poincaré famously claimed that from the state of the universe at any arbitrary point in time, its entire future is completely determined. This resembles the Stoic notion of fate, transferred to a modern event-based model of causality. For both the Stoics and Poincaré, the world is completely univocally determined. Like Aristotle, they emphasized the intelligibility of the world and of change in the world, but they made the very strong assumption of complete univocal determination. Aristotle did not.
Aristotle’s notion of intelligibility was broadly semantic, whereas Poincaré’s was mathematical. With semantic interpretation, there is always a question of how far we develop the account, which in principle could be extended indefinitely. It thus naturally lends itself to an account of incomplete determination, corresponding to some stopping point. Aristotle does not claim any more determination than he can show. Poincaré’s approach, by contrast, requires that we assume there is a complete univocal determination of the world by mathematical laws, even though we can never even come close to knowing enough to show it. This assumption leaves no room for anything like potentiality. Potentiality, it seems to me, could only have a place in a semantic approach to intelligibility.
The modern factual world is usually considered as something that just is, without modal qualification, but I have increasingly begun to doubt whether for Aristotle there is any non-modal account of the world. I read actuality and potentiality both as modal concepts, and everything in the Aristotelian world as parsable into actuality and potentiality.
What’s important about this is that potentiality is not just some mysterious “metaphysical” concept that we could maybe do without. It is a distinct logical/semantic modality supporting multiple virtual alternatives for the same thing. It allows us to intelligibly account for the incomplete determination we really experience, rather than treating real-world incompleteness and ambiguity as if it were a kind of flaw. (See also Structural Causality, Choice; Values, Causality; Structure, Potentiality.)
Potentiality and actuality are Aristotle’s indispensable modal tools, providing resources for a variety of sophisticated analyses. Notable applications include a nonreductive, “dialectical” interweaving of is and ought that allows conditional “oughts” to be constructed subsuming applicable details of a contextual “is”. This allows something like structural causality to coexist with something like Kantian freedom.
Modern discourse on the relation of “is” and “ought” has generally oscillated between a reductive ethical naturalism that explains “ought” exclusively in terms of “is” on the one hand, and an unexplainable dualism of “is” and “ought” on the other.
With his explicit distinction between modes of potentiality and actuality, Aristotle had a better way. He also talked about the typical modern modalities of abstract possibility and necessity, but concrete potentiality and actuality are the crown jewels of Aristotle’s modal discourse. (See also The Importance of Potentiality.)
Nietzsche famously criticized received notions of good and evil, and pointed out the inglorious role of “reactive” and resentful thinking about morals. To negatively frame our notions of goodness and virtue in terms of emotional reactions to bad things done by others is not an auspicious beginning for ethics. It results in a bad order of explanation that puts negative judgments of others before positive consideration of what is right.
Nietzsche pointed out that this occurs more often than we might think. A recurring emphasis on negative, blaming attitudes toward other people over affirmative values is unfortunately all too common not only in ordinary life and actually existing religious practice, but across what passes for the political spectrum. We ought to distance ourselves from this, and develop our values in positive rather than negative terms. We should aim to be good by what we do, not by contrasting ourselves with those other people. As an antidote to resentment, Nietzsche recommended we cultivate forgetfulness of wrongs done by others. I would add that we can have strong concern for justice without focusing on blame or revenge.
Like Aristotle, but without ever mentioning the connection, Nietzsche emphasized a certain sort of character development, and effectively advocated something close to Aristotle’s notion of magnanimity, or “great-souledness” as contrasted with small-mindedness. But in common with some modern interpretations of “virtue ethics”, Nietzsche tended to make whatever a presumably great-souled person might in fact do into a criterion, and consequently downplayed the role of the rational deliberation jointly emphasized by Aristotle and Kant.
Unfortunately, Nietzsche seems to have been so outraged by what he saw as widespread hypocrisy that he sometimes failed to take his own advice to avoid dwelling on the negative. This comes out in his tendency to make sweeping historical generalizations. Thus, he presented all religion in a negative light, and even went so far as to blame the “moralism” of Socrates and Plato for many later historical ills, while failing to note his own partial convergence with Aristotle.
Even at the peak of my youthful enthusiasm for Nietzsche, this negative judgment of Socrates and Plato always seemed wrong to me. Textual evidence just does not support the attribution of primarily “resentful” attitudes to either of them. On the contrary, Socrates and Plato began a completely unprecedented attempt to understand what is good in positive terms, and took great care to avoid prejudice in the process.
Partly as a consequence of his sweeping rejection of Socrates and Plato, Nietzsche looked for alternate heroes among the pre-Socratics, especially favoring Heraclitus. (In the 20th century, with different motivations, Heidegger expanded on Nietzsche’s valorization of the pre-Socratics over Plato and Aristotle, claiming that Heraclitus and Parmenides “had Being in sight” in ways that Plato and Aristotle did not. This seems to me like nonsense. As distinct from poetry and other artistic endeavors (which I value highly, but in a different way), philosophy is not about primordial vision or its recovery; it is about rational understanding and development toward an end, starting from wherever we actually find ourselves. While the pre-Socratics are important in a sort of prehistory of philosophy, the level of rational development they achieved was minimal. Extended rational development first bloomed with Plato, and then was taken to a yet higher level by Aristotle.)
Nietzsche also denied the reality or effective relevance of anything like Aristotelian potentiality, claiming that only what is actual is real. The semantic or expressive category of potentiality underwrites logical and linguistic modality, which among other things in turn underwrites the possibility of expressing objective judgments of “should”, as well as of causality, of which Nietzsche seems to have taken a Humean view. The general role of potentiality and modality is independent of all issues of the correctness or possibly prejudiced character of particular judgments.
Nietzsche’s denial of potentiality is thus related to a denial of any objective good and evil. It is akin to other views that attempt to explain values by facts. He thought mostly in terms of actually occurring valuations, and did distinguish better from worse ones, but mainly in terms of a kind of ad hominem argument from great-souledness or small-mindedness.
In my view, he should have been content to point out that many particular judgments are prejudiced or incorrect, and at any moment we have no sure way of knowing we accurately recognize which these are. Objectivity in ethics cannot be assumed as a starting point, but that does not mean there can never be any. Where it occurs, it is a relative status that is the product of a development. (See also Genealogy.)
Nietzsche’s poetic notion of the Eternal Return does in a way partly make up for his overly strong denial of any objective good or evil. The Eternal Return works especially as an ethical, selective thought that distinguishes purely affirmative valuations from others. I used to want to think this was enough to recover something objective that acts like a notion of good as affirmativeness, but that is contrary to what he says explicitly.
Why should we care about something as seemingly esoteric as modality? Without modal concepts like necessary, possible, and should, there could be no knowledge beyond mere acquaintance with particulars, and no ethics at all. Nothing we said could have any force. We could not really even form any general concepts. Nothing would really follow from anything else. The fact that necessary or should is sometimes applied in too strong a way — or that possible is sometimes applied in too abstract a way — does not negate their essential role.
I want to say that modal concepts are properly meaningful only when bound to a context. It is only the lack of proper binding to a context that makes their application too strong or too abstract.
This relation actually goes both ways. Modal assertions not limited by context sound like dogmatism or would-be despotism; but equally, an emphasis on context with no consideration of modality at all would lead to bad relativism or particularism. Modality and context have a kind of complementarity, and need to go together. Either one without the other causes trouble, but the two together ground ethics, knowledge, and wisdom. Their combination is another good example of an Aristotelian mean. (See also Modality and Variation.)
David Corfield suggests that modality has to do with ranges of variation. This seems extremely helpful. He connects Brandom’s notion of ranges of counterfactual robustness with mathematical analyses of variation. Corfield approvingly cites Brandom’s argument that in order to successfully apply empirical concepts at all, we must already be able to apply modal concepts like possibility and necessity. This always seemed right to me, but the talk about possible worlds made me worry about what sounded like impossibly strong quantification over infinities of infinities. Corfield also points out that Saul Kripke originally cautioned against uncareful extension of his possible-worlds talk.
It now seems to me that Brandom’s counterfactual robustness and Corfield’s mathematically analyzable variation together can be taken as an explanation for modal notions of necessity that previously seemed to be simply posited, or pulled out of the blue. Modality suddenly looks like a direct consequence of the structure of ranges of variation. Previously, I associated both structure and Brandom’s modally robust counterfactuals with Aristotelian potentiality, so this fits well.
Corfield also relates this to work done by the important 20th century neo-Kantian, Ernst Cassirer, on invariants behind the various systems of Euclidean and non-Euclidean geometry. He points out that Cassirer thought similar concerns of variation and invariance implicitly arise in ordinary visual perception, and connects this with Brandom’s thesis that modality is already there in our everyday application of empirical concepts.
The British Empiricist David Hume famously criticized common-sense assumptions about causality and necessity, preferring to substitute talk about our psychological tendencies to associate things that we have experienced together. Hume pointed out that from particular facts, no knowledge of causality or necessity can ever be derived. This is true; no knowledge of necessity could arise from acquaintance with particular facts. But if necessity and other modalities are structural, as Corfield suggests, they do not need to be inferred from particular facts, or to be arbitrarily posited.
The kind of necessity associated with structural determination is quite different from unconditional predestination. I want to affirm the first, and deny the second. Structural determination only applies within well-defined contexts, so it is bounded. If we step outside of the context where it applies, it no longer has force. (See also New Approaches to Modality; Free Will and Determinism.)
Leibniz is more familiar to me than Kripke, so when I hear “possible worlds”, I have tended to imagine complete alternate universes à la Leibniz. “Worlds”, however, could be read much more modestly as just referring to Corfield’s ranges of variation.
Modality is a way of formally, logically talking about what I would call the higher-order aspects of the ways of being of things. It is most commonly associated with necessity and possibility, but I think these are actually atypical examples that may give a misleading impression of what modality in general is, because necessity and possibility both have a kind of extreme all-or-nothing character that does not hold for modality in general.
I don’t believe quantification across all possible worlds could be interpretable by any process of interpretation, so I don’t consider it even intelligible in an acceptably strong sense, and I also don’t believe in unconditional necessity. Anything real or any truth about it, as well as anything I would accept as a legitimate formal construction, has conditions, even if they are only implicit. So, standard modal logic concerned with operators for these unconditional things — technical interest aside — does not seem very useful to me, because the resulting propositions would be too strong.
I am a bit surprised that Brandom is so charitable toward formal possible-worlds semantics, given his reservations about formalism in general. Technically innovative as it was, this approach seems like an extravagant extreme of infinitary classical representationalism.
Modality itself should be safe from these concerns. At a handwaving level, I imagine an indefinite number of modalities related to particular specifiable conditions, and expressing structural “degrees” or “flavors” of more specific necessity or possibility based on those conditions.
Wilfrid Sellars suggested that modalities should be understood as specific forms of normative bindingness. This seems very helpful as an alternative to extensionalist possible-worlds formalisms. (See also Why Modality?; Modality and Variation; New Approaches to Modality; Deontic Modality; Redding on Morals and Modality.)