The Evolution of Modern Metaphysics: Making Sense of Things (25 page)

So much, then, for the semantic element in Hume’s empiricism. What of the epistemic element? It is related. For just as Hume takes meaning to require a corresponding idea or ideas, so too he takes belief to require a corresponding idea. More specifically, Hume takes a belief to be an idea accompanied by a certain feeling.
¹⁹
This feeling, which he describes as a feeling of ‘vividness’ and ‘steadiness’, and which distinguishes the ideas to which it attaches from mere flights of fancy, ‘gives them more weight and influence; makes them appear of greater importance; enforces them in the mind; and renders them the governing principle of our actions’ (
Enquiry
, pp. 49–50). Now, because there is no belief without an idea, belief is subject to precisely the same constraints, as far as its origins are concerned, as meaning. One cannot believe what one cannot conceive by assembling ideas derived from previous impressions. But there is more to Hume’s epistemic empiricism than that. His epistemic empiricism concerns not just the conditions for a belief to be formed, but the conditions for it to be warranted or
to merit the title ‘knowledge’. And again Hume will insist on there being a derivation from impressions, or from sense experience.
²⁰

This time, however, the derivation will need to be more exacting. That much would be obvious if the conditions for a belief to be warranted were thought of as both necessary and sufficient. For in that case, unless the derivation were more exacting, every belief would count as warranted, just by virtue of being formed. But even if the conditions are thought of only as necessary – an issue that we can leave open – any account that deserves to be called a version of epistemic empiricism will require more of the derivation than whatever enables a belief simply to be formed. Hume’s account certainly requires more.

But how much more? Here again there is room for exegetical debate.
²¹
On one extreme view Hume denies that the derivation should use any resources other than those of pure deductive reasoning – from which it would follow that hardly any of our beliefs count as warranted. On that view Hume is fundamentally a sceptic. An apparently polar opposite view is that Hume takes for granted the warrant of most of our beliefs and accordingly allows that the derivation may use other resources, which he sees it as his business to identify. (I say ‘apparently’ polar opposite. In fact both views share a vital component. On both views Hume denies that the resources of pure deductive reasoning are sufficient to derive most of our beliefs from our impressions. But there can surely be no exegetical dispute about
that
. That is surely one of Hume’s most distinctive philosophical tenets, to be acknowledged by all parties to this debate (see
Enquiry
, §IV).)

Fortunately, this is not a debate in which we need to get involved. Given any view about what resources Hume would admit into the derivation, there will be a corresponding set of beliefs on which Hume’s epistemic empiricism thereby casts doubt, the fewer the resources, the larger the set. The largest such set will contain any beliefs that cannot be derived from our impressions using only the resources of pure deductive reasoning. But that is not what really matters from our point of view. What matters from our point of view is the smallest such set, the set of beliefs on which
all
parties to the debate will agree that his epistemic empiricism casts doubt. And to determine what that is, we need only determine what the corresponding view about the resources is. In effect, then, our question is this: what is the largest set of resources that anyone could reasonably think Hume would admit into the derivation?

The answer, I suggest, is the set of resources that we
in fact
use, as a matter of basic human nature, when we proceed from our impressions to our
beliefs. If this suggestion is correct, then of course the devil in the detail of ‘derives from’ is now in the detail of ‘as a matter of basic human nature.’ (In particular, there are difficult questions about how natural it is for us to form religious beliefs of various kinds, questions with which Hume wrestles in his
Natural History of Religion
.
²²
) But I think this is just what we should expect. For I take Hume’s own primary concern to be precisely with developing a science of human nature, be the warrants for our beliefs as they may.
²³
This means, among other things, that he wants to explore the various natural processes whereby human beings arrive at their beliefs. My suggestion is that any beliefs arrived at by processes that cannot be duly assimilated to the most basic of these natural processes will not constitute sense-making for Hume, on any epistemic interpretation of ‘sense-making’.
²⁴

But I also claim, conversely and crucially, that any beliefs arrived at by processes that
can
be duly assimilated to the most basic of those natural processes
will
constitute sense-making for Hume,
on at least the most liberal epistemic interpretation of ‘sense-making’
. For these are the beliefs on the strength of which we in fact negotiate our way through the world and conduct our various affairs, again be the warrants for them as they may. Certainly, they would constitute, for Hume, ‘a reliable and workable conception of what things are like’, to use the phrase that I used in §1.
²⁵
This further explains the irrelevance to our concerns of the debate above. Relative to our concerns, that debate is little more than a terminological dispute about how to use the word ‘warrant’.
²⁶
It does not significantly affect
Hume’s conception of the scope and limits of sense-making, on the liberal interpretation of ‘sense-making’ which I am, appropriately enough in this context I take it, adopting.

The question now, therefore, is: what are the relevant natural processes?

3. Relations of Ideas and Matters of Fact

It is far beyond the scope of this chapter to give anything but the merest sketch of an answer to this question. But the crucial point is that these processes are of two fundamentally different kinds, issuing in beliefs of two fundamentally different kinds. Processes of the first kind are those of pure deductive reasoning, in abstraction from any of our particular impressions. The beliefs in which these issue are beliefs about how our ideas are related to one another.
²⁷
Processes of the second kind issue in beliefs about how our ideas and impressions are related to what lies beyond them. Although these too include pure deductive reasoning, at their core is an appeal to causal connections.

Here is Hume:

All the objects of human reason or enquiry may naturally be divided into two kinds, to wit,
Relations of Ideas
, and
Matters of Fact
. Of the first kind are the sciences of Geometry, Algebra, and Arithmetic; and in short, every affirmation which is either intuitively or demonstratively certain.
That the square of the hypothenuse is equal to the square of the two sides
, is a proposition which expresses a relation between these figures…. Propositions of this kind are discoverable by the mere operation of thought, without dependence on what is anywhere existent in the universe. Though there never were a circle or triangle in nature, the truths demonstrated by Euclid would for ever retain their certainty and evidence.
²⁸

Matters of fact, which are the second objects of human reason, are not ascertained in the same manner…. The contrary of every matter of fact … is conceived by the mind with the same facility and distinctness, as if ever so conformable to reality.
That the sun will not rise to-morrow
is no less intelligible a proposition, and implies no more a contradiction, than the affirmation,
that it will rise
….

All reasonings concerning matters of fact seem to be founded on the relation of
Cause and Effect
. By means of that relation alone we can go beyond the evidence of our memory and senses. If you were to ask a man, why he believes any matter of fact, which is absent; for instance, that his friend is … in France; he would give you a reason; and this reason would be some other fact; as a letter received from him…. If we anatomize all the other reasonings of this nature, we shall find that they are founded on the relation of cause and effect…. (
Enquiry
, pp. 25–27, emphasis in original)

This is reminiscent of Leibniz’ distinction between truths of reasoning and truths of fact (see §4 of the previous chapter).
²⁹
Like Leibniz’ distinction, it is meant to signal a fundamental dichotomy between what we can ascertain by the inspection and analysis of our ideas and what we can ascertain only by appeal to experience and the principles of extrapolation fitted to it. There is no middle ground. Nothing can be known by, say, divine revelation, or by some sort of
a priori
insight into the structure of reality. There can be no sense-making, even on the most liberal epistemic interpretation of ‘sense-making’, that is not derived in one of these two ways from sense experience.

Hume is typically self-conscious about this. He realizes that his strictures must apply, in particular, to his own attempts to make sense of things. That is why he is keen to emphasize that he himself is using ‘the experimental method of reasoning’.
³⁰
He takes himself to be developing a conception of the human mind, and its various operations, by appeal to causal connections that he has discerned between episodes in his own and other people’s thinking (e.g.
Enquiry
, §I).
³¹

Similarly, he wants to be sure that he is respecting his semantic empiricism. In particular, he wants to be sure that he is doing this when he makes claims about causation. That is one reason why such a large part of his enquiry is devoted to a search for the impression from which the idea of a (causally) necessary connection derives. He eventually concludes that the relevant impression is the ‘customary transition’ which is felt in the mind when, ‘after a repetition of similar instances, the mind is carried by habit, upon the appearance of one event, to expect its usual attendant’ (
Enquiry
, p. 75; cf.
Treatise
, pp. 266–267, and ‘Abstract’, pp. 656–657). Thus suppose that every time I see the striking of a ball by a bat I immediately thereafter see a deviation of the ball from its previous course. And suppose that my mind is so constituted that, after this has happened a few times, my seeing the striking of a ball by a bat induces in me the expectation that the ball will once again deviate from its previous course. Then the feeling I have of this inducement is the impression from which my idea of a (causally) necessary connection derives.
³²

Hume is reasonably confident, then, that his empiricism has no adverse consequences for his own attempt to make sense of things.
³³
But what are its consequences for metaphysics, the most general attempt to make sense of things?

4. Metaphysics as an Experimental Science of Human Nature

There are some immediate negative consequences that are obvious, and some immediate positive consequences that are only a little less obvious.

On the negative side, metaphysics affords no more prospect than any other enquiry for sense-making that does not derive from sense experience. Or, as we could also say, we have no more scope in metaphysics than we do in any other enquiry for making sense of what is transcendent (see the Transcendence Question from §6 of the Introduction).

As we have seen, this is partly a semantic matter, partly an epistemic matter. Insofar as it is a semantic matter, then it provides another instance of the
pattern noted in
Chapter 2
, §2. There is, in Hume, a recoil from attempts in earlier philosophers to make sense of what is transcendent, grounded in the conviction that there is no
sense
there to be made. I have already noted some of the casualties; see §2.

Insofar as it is an epistemic matter, then it curbs our aspirations to establish, by reasoning of any kind, that whose ‘best and most solid foundation is faith and divine revelation’ – as Hume puts it, with what we must surely regard as characteristic irony – for instance ‘the existence of a Deity, and the immortality of souls’ (
Enquiry
, p. 165, emphasis removed; cf. ibid., §XII, Pt III, passim). For Hume, the word ‘metaphysics’ sometimes serves as a label for just the sort of thing that is thereby precluded.
³⁴
On that understanding of metaphysics, his work is an assault on the very possibility of metaphysics.

But, as I emphasized in §§2 and 3 of the Introduction, provided that metaphysics is understood as nothing but the most general attempt to make sense of things, then it is not subject to any such assault. There can at most be controversy about how it is to be pursued or what it can achieve.
³⁵
And here we see the positive consequences of Hume’s empiricism for metaphysics. To whatever extent his empiricism directs his own attempts to make sense of things, it directs the most general attempt to make sense of things. For, as Hume himself insists, his own attempt to make sense of things is, precisely, an attempt to do so at the highest level of generality. In his introduction to the
Treatise
he writes: