The Aristotelian Causes in Hume

When by natural principles we [humans] are led to advance those ends, which a refined and enlightened reason would recommend to us, we are very apt to impute to that reason, as to their efficient cause, the sentiments and actions by which we advance those ends, and to imagine that to be the wisdom of man, which in reality is the wisdom of God. Upon a superficial view, this cause seems sufficient to produce the effects which are ascribed to it; and the system of human nature seems to be more simple and agreeable when all its different operations are in this manner deduced from a single principle.---Adam Smith The Theory of Moral Sentiments 2.2.3.5

Yesterday, I noted that one way to understand Hume's significance to our conceptualization of causation is two-fold: first, that he whittled down four Aristotelian causes to just one kind of cause (previously known as 'efficient causation'); and, second, that he is the source of the modern conception of causation by offering a counterfactual definition of it in the first Enquiry. Hume is also taken to be the source of our modern discussion of convention, (recall here) although a very good argument can be made that Hume is greatly indebted to Locke (see also this more recent post and this one as a follow up). In today's post I suggest that Hume's account of convention itself is greatly indebted to the Aristotelian causes. Let me explain by first re-quoting a familiar passage from Hume: 

But if by convention be meant a sense of common interest; which sense each man feels in his own breast, which he remarks in his fellows, and which carries him, in concurrence with others, into a general plan or system of actions, which tends to public utility; it must be owned, that, in this sense, justice arises from human conventions. For if it be allowed (what is, indeed, evident) that the particular consequences of a particular act of justice may be hurtful to the public as well as to individuals; it follows, that every man, in embracing that virtue, must have an eye to the whole plan or system, and must expect the concurrence of his fellows in the same conduct and behaviour. Did all his views terminate in the consequences of each act of his own, his benevolence and humanity, as well as his self-love, might often prescribe to him measures of conduct very different from those, which are agreeable to the strict rules of right and justice.

In the posts linked above I argued that Hume's analysis of convention has eight parts (most also to be found in Locke's Second Treatise and the Essay):

1. a sense of common interest
2. felt in each person's breast;
3. It (viz, (i)) is observed in others;
4. this fact (the existence of (i&iii) creates collaboration & reliable expectations;
5. the collaboration is structured in non-trivial ways;
6. and this has good consequences or positive externalities for society.
7.  A Humean convention is explicitly contrasted with practices founded in explicit promises and/or in practice regulated by formal governmental law. In addition,
8.  the process (I-III) need not be verbalized at all. It can be entirely tacit.

I call I-VIII: ‘the Humean template,’ and they are jointly sufficient, although (VII) is not necessary.

Now, the Humean template has quite a few moving parts. And given that in Locke the Humean template is used but, as far I am aware, not explicitly analyzed it's worth asking to what degree he would have been fully conscious of the Humean template. It's always a risk with the kind of structuralist analysis I offer here that it is merely a projection of the historian onto an earlier text. Even if that were so it can still be illuminating, of course, but to use the 'Humean template' about Locke would be straightforward anachronism (albeit useful anachronism).

But even though Locke does not explicitly analyze the Humean template, i don't think it's a mere projection on my part for three reasons (the first two of which outlined in the linked posts): first, as I realized by reflecting on work by Martin Lenz (Socializing Minds) Locke is clearly responding to lacunae in Puffendorf's account of the origin and stability of conventions. Second, the Humean template can be found in the second Treatise and the Essay (and is evoked later in the Essay). These two reasons are internal to Locke's project.

In addition, third, we can discern the portfolio of Aristotle's four causes in the Humean template. For, (VI) is the final cause(s) of a convention.  And (I) is the formal cause. In addition, (II-V) are the efficient and material causes of the convention. I mix these causes here because jointly they tie the formal and final cause together in the workings of the convention.

If Locke's use of the Humean template presupposes the Aristotelian causes then it's also no surprise that he doesn't need to offer an explicit analysis of the Humean template. His readers would have noticed it without his saying so. In Hume, the template is made explicit precisely because a reader familiar with Hume's philosophy cannot take for granted that Hume would draw on the non-efficient Aristotelian causes.

That (VI) is a final cause strikes me as uncontroversial. But it is surprising to find it in Hume, who is really an explicit and implicit critic of final causes (see here also for references). Of course, in virtue of providing the mechanism for its functionality one may well say that the Humean template naturalizes or presupposes a naturalized teleology. One may also claim that in human affairs, a certain kind of intentionality and goal directed is inelimenable.

The real question here is to what degree the common interest that a tacit convention secures is fully foreseaable and articulable ahead of time. For example, Adam Smith famously criticized the deployment of the Humean template in Hume's account of the origin of justice in circumstances that echo a state of nature because Hume's account seems to presuppose awareness of the final cause, or at least assume common interest, in a context where this sense of unity or mutual loyalty, seems unlikely. (See here for the full story.)

The passage at the top of the post is near the conclusion of Smith's diagnosis of the error in Hume. Interestingly enough, in Part II of the Elements of the Philosophy of the Human Mind, Dugald Stewart notes Smith's criticism of Hume, and quotes the passage in order to illustrate "a common error," which Stewart associates with the "dangerous" revitalisation of utilitarianism (he explicitly discusses Paley and Godwin in context). Stewart praises Adam Smith because "he always treats separately of their final causes, and of the mechanism, as he calls it, by which nature accomplishes the effect; and he has even been at pains to point out to his successors the great importance."

To be sure, Smith's criticism does not touch all instances of Hume's use of the Humean template. For, in some contexts the common interest is knowable even known and the efficient and material causes of the Humean template can do their work without presupposing that all the benefits from the convention are presupposed in the mechanism that gives rise to the convention or that these benefits are or would have to be obscure to the agents involved. 

This problem does not even arise in Locke. For, of course, the natural reading of much of Locke's writings is that he embraces a God given providential order. (But recall this post for the debate.) So, in Locke the use of the Humean template is completely natural and without a blemish of inconsistency.* 

* I am not denying that Aristotelian formal and material causes get reinterpreted in Locke. I am grateful to discussion with Susan James, Martin Lenz, Charles Wolfe, Spiros Tegos, Katarina Peixoto and others in Budapest.