Hume on Causes

The great British empiricist philosopher David Hume (1711-1776) wrote that “There are no ideas which occur in metaphysics more obscure and uncertain than those of ‘power’, ‘force’, ‘energy’, or ‘necessary connection'” (An Inquiry Concerning Human Understanding, Library of Liberal Arts ed., p. 73).

Hume is most famous for his critique of naive or dogmatic assumptions about causality. “[T]here is not, in any particular instance of cause and effect, anything which can suggest the idea of power and necessary connection” (p. 75). To me, it seems to be the idea of an underlying power or force responsible for causality that he is mainly questioning. He has no doubt that we continually experience instances of cause and effect.

“[There is] no such thing as chance in the world” (p. 69). “[T]he conjunction between motives and voluntary actions is as regular and uniform as that between the cause and effect in any part of nature” (p. 98). Clearly, then, he did believe in the reality of cause and effect, but only wanted to reject naive claims about our knowledge of the world that purport to link experienced instances of cause and effect to explanations in terms of the operation of underlying powers. What we actually experience in these cases is just lawful regularity.

“It is certain that the easy and obvious philosophy will always, with the generality of mankind, have the preference above the accurate and abstruse…. The fame of Cicero flourishes at present, but that of Aristotle is utterly decayed” (pp. 16-17). But on the other hand, “All polite letters are nothing but pictures of human life in various attitudes and situations…. An artist must be better qualified to succeed in this undertaking who, besides a delicate taste and a quick apprehension, possesses an accurate knowledge of the internal fabric, the operations of the understanding, the workings of the passions…. However painful soever this inward search or inquiry may appear, it becomes in some manner requisite to those who would describe with success the obvious and outward appearances of life and manners…. Accuracy is, in every case, advantageous to beauty, and just reasoning to delicate sentiment. In vain would we exalt the one by depreciating the other” (p. 19). Clearly, then, Hume’s polemic against scholastic modes of reasoning does not at all mean he simply rejects the values of “accurate and abstruse” philosophy.

Neoplatonizing tendencies in the Aristotelian commentary tradition led to the common Latin scholastic view of causes as metaphysical powers operating behind the scenes that Hume is mainly concerned to criticize. Aristotle himself identified causes more broadly and much less speculatively with every kind of “reasons why” things are as they are and behave as they do. He did so without making extravagant claims to certain knowledge. Whereas scholastic philosophers characteristically debated the pros and cons of accepting various abstract propositions, Aristotle himself was fundamentally concerned with the use of reason to help interpret concrete human experience (see Aristotelian Causes).

Hume is a great philosopher, and so far I have focused on a positive appropriation of his work, having some points in common with themes I have been pursuing about causality and the notion of power. Robert Brandom’s innovative reading of Kant’s response to Hume points out that there are distinct limits to Hume’s approach.

“Kant read Hume’s practical and theoretical philosophies as raising variants of a single question. On the side of practical reasoning, Hume asks what our warrant is for moving from descriptions of how things are to prescriptions of how they ought to be. How can we rationally justify the move from ‘is’ to ‘ought’? On the side of theoretical reasoning, Hume asks what our warrant is for moving from descriptions of what in fact happens to characterizations of what must happen and what could not happen…. Hume’s predicament is that he finds that even his best understanding of facts doesn’t yield an understanding of either of the two sorts of rules governing and relating those facts, underwriting assessments of which of the things that actually happen (all he thought we can directly experience) ought to happen (are normatively necessary) or must happen (are naturally necessary).”

“Kant’s response to the proposed predicament is that we cannot be in the situation that Hume envisages: understanding matter-of-factual empirical claims perfectly well, but having no idea what is meant by modal or normative ones” (Brandom, Reason in Philosophy, p. 54).

Brandom continues, “To judge, claim, or believe that the cat is on the mat, one must have at least a minimal practical ability to sort material inferences in which that content is involved (as premise or conclusion) into good ones and bad ones, and to discriminate what is from what is not materially incompatible with it. Part of doing that is associating with those inferences ranges of counterfactual robustness…. So, for example, one must have such dispositions as to treat the cat’s being on the mat as compatible with a nearby tree being somewhat nearer, or the temperature a few degrees higher, but not with the sun being as close as the tree or the temperature being thousands of degrees higher. One must know such things as that the cat might chase a mouse or flee from a dog, but that the mat can do neither, and that the mat would remain essentially as it is if one jumped up and down on it or beat it with a stick, while the cat would not. It is not that there is any one of the counterfactual inferences I have mentioned that is necessary for understanding what it is for the cat to be on the mat. But if one makes no distinctions of this sort — treats the possibility of the cat’s jumping off the mat or yawning as on a par with is sprouting wings and starting to fly, or suddenly becoming microscopically small; does not at all distinguish between what can and cannot happen to the cat and what can and cannot happen to the mat — then one does not count as understanding the claim well enough to endorse it” (pp. 54-55).

Brandom concludes, “If that is right, then in being able to employ concepts such as cat and mat in ordinary empirical descriptive claims one already knows how to do everything one needs to know how to do in order to deploy concepts such as possible and necessary — albeit fallibly and imperfectly” (p. 55).

I am actually a little more sympathetic to Hume, in that I don’t read him as categorically rejecting the validity of concepts of necessity, only any possibility of certain knowledge of how they apply to the real world. I personally like the position of Leibnitz that necessity is real but always hypothetical, never categorical. But Brandom is right that Hume does not go on to emphasize how essential our fallible understanding of necessity is to our understanding of ordinary experience.

Toward Self-Consciousness

The Force and Understanding chapter of Hegel’s Phenomenology concludes with two sections I find particularly difficult.

In the first, the supersensible in comparison with the world of appearances is treated as a sort of “inverted world” where negation and universality rather than concrete form play the main role in intelligibility as law. The subsequent return to the world of appearances that explains it as law-governed and takes us back to positive things again is then described as a “second inversion”.

According to Harris in his commentary, Hegel wants to establish that the formal necessity of mathematics is insufficient to account for the rationality of experience. The Understanding wants to explain everything in terms of force, including the Understanding itself. All the movement of explanation is in the Understanding. Hegel argues that the explanation of necessity in the world turns out to presuppose free activity in the Understanding. The fixing of distinctions Hegel meanwhile associates with sensuous representation as distinct from the supersensible.

In the second, what Hegel wants to call a kind of infinity emerges from Understanding’s looking at the world of appearances as a law-governed but constantly moving and restless whole that is unconditioned by anything other than itself.

Harris notes that this infinity is a result. Because infinity or the absolute is a result rather than a starting point, Hegel is able to say that the old neoplatonic problem of how the Many emerge from the One does not arise for him. Harris says Hegel is here making an Aristotelian response to Plotinus.

“Our approach to this problem has shown that Unity and Multiplicity are logically internal to one another, that the real Infinite must embrace the finite because the Infinite is precisely the raising of finitude to Infinity. This is how we can express the significance of the ‘second inversion’ in the speculative-theological terminology of finite and Infinite” (Hegel’s Ladder I, p. 303).

Because the Understanding wants to explain everything and everything includes itself, its own momentum pushes it toward self-consciousness. At this stage, what Hegel will call the Concept with a capital “C” — which will become the new continuum, folded upon itself, between subject and object, that displaces the substantiality of both in their separate forms — has yet to emerge. Hegel says that for the Understanding, what plays the role of the Concept is the Understanding itself.

Harris says “The human desire to know — to understand the situation we are in — is the most primitive way in which the Absolute is with us from the start…. The world of which the true Infinite really is the ‘soul’ is the world of our quest for the absolute truth. Our quest itself is the ‘spirit’ — the self-consciousness — of that living soul…. The understanding intelligence is the self-consciousness of the unconditioned universal that it contemplates.”

“The Understanding remains naive in its self-enjoyment; it keeps positive and negative, attraction and repulsion, all separate from one another, and from itself. It knows nothing of the ‘second inversion’. But the comprehension of the necessary relation a priori of the opposite moments of all its concepts is what the Understanding is, because it moves continually from the organized appearance to its concepts, and back again” (pp. 303-304).

“The theoretical Understanding has the whole world before it as an object. In the ‘second inversion’ it becomes aware of itself as the positing activity for the whole cycle that moves from perception (the ‘play of forces’) to the natural order as ‘Law’. But now that ‘free self’ (the ‘distinguishing of the undistinguished’) actually distinguishes itself and asserts its independence, without having any consciousness of the cycle from which it has logically emerged. It will discover by experience what the Fichtean philosophical Ego cannot help knowing from the first: ‘that this distinct [self] is not distinct’. It will make this discovery many times, in different ‘shapes’, before it returns finally to the practical comprehension of its identity with the ‘Infinite'” (pp. 305-306; brackets and italics in original).

“The truth for us… is that the universal concept of Force (or Necessity) has become the universal concept of Life (or the ‘true Infinite’ as living Freedom). But if we look at what has happened from the point of view of Understanding itself, two worlds have come into being. There is the world of Necessity which the Understanding wants to construct, but can never be sure that it has successfully duplicated; and the world of its own intellectual activity. In this second world it experiences itself as a free motion. It does not know that these two worlds are moments of one Concept, which is equally the objective world and itself as intelligence. But it does know, necessarily, that it is alive and free in the world of necessity that appears to it. It still has to discover that it is identically what appears. But it knows that it is what is appeared to” (p. 307).

“[F]rom the conscious certainty that the Understanding has of its eternal truth, we have thus come back to the certainty of the peasant-wife that this farmyard and these cows are hers. We know now, why she would not come with us on our theoretical odyssey. She was the self at home in its world; and that meant that she already knew something that we were ignoring. Truth, we thought, is an absolute object. It cannot belong to anyone. Frau Bauer, on the other hand, realized that in order to know anything one must be alive” (p. 318). (Later, it will also turn out that we were right that truth cannot belong to anyone.)

“As the implications of my identification with another self-consciousness which exemplifies what I want to be are unpacked, we shall discover that the supposedly ‘supersensible’ world is the real present world that we live in; or that ‘the spirit’ is the real substantiality of our sense-experience” (p. 335).


The final part of Paul Ricoeur’s Freedom and Nature was to discuss our “aquiescence to necessity” (p. 341). At one point he says he is looking for a way to ground something like Nietzsche’s amor fati or “love of fate”. The idea would be to explain how to achieve reconciliation to what must be, but without falling into an overly passive stance. Here he notes that “Pure description raises more problems than it resolves or than it presents as resolved” (p. 347).

His attempts to describe various aspects of necessity — principally under the forms of character, the unconscious, and life, which he notes also involve other wills, history, and the whole course of nature — he finds to be irremediably tainted by the “spell of objectivity” (ibid). The problem seems to be that he honestly thinks empirical data — or psychoanalytic theories, in the case of the unconscious — give the best insight into the operations of “bodily necessity” (p. 343), but then his Marcellian concerns about objectification lead him to conclude that none of the work he surveys in this context is usable for achieving the kind of reconciliation he wanted.

He ends up hinting that this will be resolved in a future work that does not rely on a Husserlian “bracketing” of questions related to what Ricoeur calls Transcendence that he had announced would limit the scope of this work. Transcendence, he suggests, will be addressed in the new context of a “poetics” of the will, rather than the modified Husserlian phenomenology he was pursuing here. He seems to have believed that ultimate reconciliation of freedom and necessity could only be achieved through a spiritual relation to Transcendence. Without in any way diminishing the value of such a spiritual relation, I am more optimistic that there is a purely philosophical resolution of this issue, using Aristotelian and Brandomian resources. Meanwhile, having myself already used the term “poetic” to describe statements about spiritual beliefs, I look forward to seeing how he developed this notion of a “poetics”. (See also Phenomenology of Will; Ricoeur on Embodiment; Ricoeur on Choice; Voluntary Action.)

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.)