One of my favorite passages from Hume actually occurs twice – in the Treatise and the Enquiry. This is the passage where Hume offers up the example of the man with normally functioning faculties who is suddenly placed into a strange, unfamiliar environment. This is the lesson Hume draws from this thought experiment:
For ‘tis evident, that if a person full-grown, and of the same nature with ourselves, were on a sudden transported into our world, he wou’d be very much embarrass’d with every object, and would not readily find what degree of love or hatred, pride or humility, or any other passion he ought to attribute to it. The passions are often vary’d by very inconsiderable principles; and these do not always play with a perfect regularity, especially on the first trial. But as custom and practice have brought to light all these principles, and have settled the just value of every thing; this must certainly contribute to the easy production of the passions, and guide us, by means of general establish’d maxims, in the proportions we ought to observe in preferring one object to another. (T 2.1.6, 293-4)
In the Enquiry Hume slightly modifies the example:
Suppose a person, though endowed with the strongest faculties of reason and reflection, to be brought on a sudden into this world; he would, indeed, immediately observe a continual succession of objects, and one event following another, but he would not be able to discover any thing farther. He would not, at first, by any reasoning, be able to reach the idea of cause and effect; since the particular powers, by which all natural operations are performed, never appear to the senses; nor is it reasonable to conclude, merely because one event, in one instance, precedes another, that therefore the one is the cause, the other the effect. Their conjunction may be arbitrary and casual. There may be no reason to infer the existence of one from the appearance of the other. And in a word, such a person, without more experience, could never employ his conjecture or reasoning concerning any matter of fact, or be assured of any thing beyond what was immediately present to his memory and senses. (EHU 36).
In both quotes what is of interest for me is the process whereby the strangeness of the encounter is resolved. For Hume it is indeed a problem to account for how we come to individuate the beliefs and passions that we do. There are no guarantees, and as I’ve argued elsewhere, Hume is aware that delusion is always a possibility. The mad person may, as Hume points out, acts such that “every loose fiction or idea [has] the same influence as the impressions of memory,” and as a result “a present impression and a customary transition are now no longer necessary to inliven our ideas.” (T 123) Such delusions and madness are largely avoided, however, and it is precisely the problem of accounting for this avoidance that is of interest for me in the two passages cited above. One notable difference between these passages is that in the Treatise Hume turns to “custom and practice” as the explanation for the “regularity” of the “general establish’d maxims” that guide our passions toward their proper targets. This account will also bring to bear the important role institutions and social context play as sedimented forms of custom and practice. Hume is certainly aware of this and it becomes an important theme in his essays.
In the passage from the Enquiry, Hume argues that the person suddenly transported into this world would be unable to discern any causal relations between the succession of objects they perceive, but then he goes on to admit that “the particular powers, by which all natural operations are performed, never appear to the senses…” In other words, whereas the strangeness of the encounter is overcome, on the account offered in the Treatise, by way of custom and practice, the Enquiry account will highlight the importance of custom and practice and the inaccessibility of the “particular powers, by which all natural operations are performed.” This has led Hume scholars to argue that despite the apparent skepticism one finds in Hume’s thought, especially in the closing pages of Part 1 of the Treatise, by the time of the Enquiry Hume had become a realist regarding the “particular powers” or causal laws that are what ultimately account for the regularity one finds within the “continual succession of objects” of one’s experience. This debate among Hume scholars has come to be called the New Hume debate (see this).
Without rehearsing the arguments in the New Hume debate, I want to move towards a key Deleuzian extension of Hume’s arguments (which I’ll take up in more detail in the next post) – namely, the principle of sufficient reason (PSR). As Michael Della Rocca has argued (here), Hume comes surprisingly close to affirming the PSR. If the PSR asserts that for every thing there is a reason or cause for why it exists, then the standard line for Hume is that the separation “of the idea of a cause from that of a beginning of existence, is plainly possible for the imagination,” and with this we have Hume’s argument against the PSR. Since one can plainly conceive an object separate from, and distinct from that which is to serve as its cause or explanation, then one can clearly, as Hume would have us conclude, do without the PSR. One need not conceive of an object in relation to its PSR. As Della Rocca shows, however, following Garrett, the pivotal move in Hume’s argument is to claim that that which is distinguishable is at the same time separable. A counterexample to this move would undermine Hume’s argument, and yet to argue for the reality of “particular powers” by which “all natural operations are performed,” and powers moreover that “never appear to the senses,” it seems that Hume has indeed distinguished these powers from what is perceived and yet these powers are, on Hume’s account, inseparable from the regularity we do perceive. Has Hume, despite himself, undermined his own anti-rationalist arguments and given support in the end to the PSR?
As Della Rocca argues, Hume does appear at times to have strong tendencies that lead him in a rationalist, PSR-supporting direction, but this makes his anti-rationalist move all the more challenging and forceful, Della Rocca claims. The key move in Hume’s anti-rationalist argument, Della Rocca claims, turns on the separation of the cause from its effect, or upon the assertion that there are a multiplicity of distinct objects, objects that are then taken to be (or not) in causal relations with each other (Della Rocca sidesteps the New Hume debate, though it is critical, as I will argue in my next post, to understanding the Deleuzian extension of Hume). It is this move that the supporter of the PSR must deny; or, as Della Rocca puts it, “Hume’s argument against the PSR and rationalism is, in effect to point out that the only consistent form of rationalism is one that accepts a form of monism and denies any multiplicity of distinct objects.” But this is precisely what Spinoza does. He bites the bullet and accepts monism at the expense of a multiplicity of distinct objects. Deleuze, moreover, goes even further and accepts monism and the PSR and he affirms a metaphysics of multiplicity, though this is not a multiplicity of distinct objects for precisely the reason that this multiplicity is the PSR for the individuation of distinct objects. It is here where Deleuze’s extension of Hume’s project becomes most pronounced, and it is this theme that will be the subject of my next post.