The Evolution of Modern Metaphysics: Making Sense of Things (11 page)

Why should the fact that I cannot doubt something, when I clearly and distinctly perceive it to be true, mean that it is true?

Those who embrace a certain kind of idealism will respond to this question by appeal to a constitutive link between clear and distinct perception and truth. And where metaphysical issues are concerned, this will include those, or at least some of those, whose response to the Creativity Question from §6 of the Introduction is to say that metaphysics is a fundamentally creative exercise. But Descartes has no sympathy for anything of that sort.
¹⁵
His own celebrated response to the Reflective Question begins with the one
instance of it to which he can see an immediate answer, that in which what is at issue is his own existence. Why should the fact that he cannot doubt that he exists, when he clearly and distinctly perceives it to be true, mean that it is true? Because if it were not true, he would not be in a position clearly and distinctly to perceive anything, nor to doubt anything, nor to be unable to doubt anything. In a word, he would not be in a position to
think
.
¹⁶
‘I think,’ Descartes famously says, ‘therefore I am’ (
Discourse
, VI: 32; cf.
Meditations
, VII: 25).

What is distinctive about this case, we now see, is not that it is the one case in which there is an indubitability. For, in the relevant sense of indubitability, there are very many cases in which there is an indubitability. What is distinctive about this case is that it is the one case in which the indubitability, viewed from a position of general reflection, provides its own immediate warrant.

But ‘the one case’ is the operative phrase. That Descartes has a guarantee of his own existence does not advance his cause very much. How does he proceed from here?

While he is contemplating his own existence he also focuses on various characteristics of himself, including the fact that he has an innate idea of God, an infinite Being whose infinitude, crucially, includes benevolence. Drawing on some of his scholastic heritage, as advertised earlier in §1, and in particular drawing on the principle that ‘there must be at least as much reality in the efficient and total cause as in the effect of that cause’, he argues that only God could have placed such a grand idea in him, and hence that God must exist (
Meditations
, VII: 49–51).
¹⁷
But God, granted His benevolence, would not allow Descartes to be deceived when he is doing all within his powers to discover the truth. So Descartes does after all have a general answer to the Reflective Question: the fact that he cannot doubt something, when he clearly and distinctly perceives it to be true, does mean that it is true because the alternative would be contrary to God’s benevolence (
Fourth Meditation
).

Plainly, Descartes could not have made any kind of progress here, even in his own terms, had he not allowed himself to interrupt his general reflection on what he believes by directing his attention, as the need arises, to principles that he clearly and distinctly perceives to be true, principles that he cannot at the same time doubt, and then appropriating those principles. Examples are the principle that his thinking implies his existing, and the scholastic principle just mentioned about cause and effect (see e.g.
Replies
, VII: 135 and 145–146). Before we consider a natural objection to which this
gives rise, it is worth pausing to consider what form the indubitability of these principles takes. This will enable me to say how I reconcile the second of my opening claims in this chapter with the second of the two items of common exegetical knowledge.

The fact that we cannot doubt these principles, when we clearly and distinctly perceive them to be true, is of a piece with the fact that we cannot conceive them to be false; that their falsity would, as Descartes puts it, ‘conflict with our human concepts’ (
Replies
, VII: 150). But for their falsity to conflict with our human concepts, Descartes says in the same context,
just is
for them to be necessary. That is how Descartes understands necessity. Nor is there any suggestion that this is a relativized necessity, of the same sort as the relativized possibilities considered earlier.
¹⁸
So it follows that not even God could have made one of these principles false. If it conflicts with our human concepts that somebody should think without existing, or that one plus two should not be three, then it conflicts with our human concepts that God should have made somebody think without existing, or that God should have made one plus two other than three (cf.
Meditations
, VII: 71).

What then of the item of common exegetical knowledge, that both the truth and the necessity of any necessary truth depend on God’s free choice (e.g.
Replies
, VII: 432 and 436; cf. ‘Letter to Mersenne’, dated 15 April 1630, in
Correspondence
, I: 145, and ‘Letter to Mersenne’, dated 6 May 1630, in
Correspondence
, I: 149)? There is simply no conflict. Dependence here need not be understood in terms of the exclusion of possibilities. That thinking implies existing; and that it is necessary that thinking implies existing, in other words that our human concepts conflict with thinking’s failing to imply existing: these can be regarded, for current purposes, as two data. Descartes’ view is that, like everything else, they depend on God’s free choice. The first holds because of how God has made thinking; the second holds because of how God has made us. But we should not say that, in making thinking thus, God has excluded other possibilities, nor that, in making us thus, He has prevented us from grasping other possibilities.
For there are no other possibilities
. To suggest that there are would simply be to violate the second datum: that it is necessary that thinking implies existing.

(It is only fair for me to add that not everything that Descartes says fits comfortably into this account of his views. Most notably, we find the following in a letter to Antoine Arnauld:

I do not think we should ever say of anything that it cannot be brought about by God. For since every basis of truth … depends on his omnipotence, I would not dare to say that God cannot make [it] … that one and two should not be three. I merely say that he has given me such a
mind that I cannot conceive … an aggregate of one and two which is not three, and that such [a thing involves] a contradiction in my conception. (‘Letter to Arnauld’, dated 29 July 1648, in
Correspondence
, V: 224)

It seems to me that Descartes is being over-cautious here. I think he is at perfect liberty, by his own lights, to say what he ‘would not dare to say’.
¹⁹
There is admittedly the complication that we might be able to conceive, in the abstract if not in detail, God’s making something true that conflicts with our human concepts while changing our concepts so as to remove the conflict, or even, for that matter, God’s making something true that conflicts with our human concepts and allowing the conflict to remain – provided that in the latter case we prescind from His benevolence. But neither of these, strictly speaking, precludes our saying, of any particular thing that conflicts with our human concepts, that God cannot make it true. These considerations about how our human concepts and their relations with reality might have been different would in any case have little impact on Descartes’ account of modality if that account were intended, not as an
analysis
, but rather as some version of what Simon Blackburn calls ‘quasi-realism’. On a suitably quasi-realist understanding, ‘It is necessary that’ is not to be analyzed as (is not equivalent in meaning to) ‘It conflicts with our human concepts that it should not be the case that’; rather, the former serves as an expression of the conflict referred to in the latter (see Blackburn (
1993b
)). This certainly allows for the necessity to be as robust as I am suggesting it is on Descartes’ conception. For it allows for statements of necessity which, because they do not have our human concepts and what conflicts with them as their subject matter, are not under any direct threat from considerations about how these might have been different.
²⁰
I do not however claim that Descartes himself has a quasi-realist understanding of these matters. Not only would it be anachronistic to do so; it would make the caution which already causes some exegetical difficulty for me cause even more. One final point in connection with this caution: when Descartes refuses to rule out the possibility that God should have made one plus two other than three, even though such a thing is unintelligible to us, he provides the first hint in this historical narrative of a general problem to which, or to one version of which, I referred in §6 of the Introduction, namely that there is no way of registering the thought that our sense-making is limited in this or that respect except by transgressing the limit.)

Descartes allows himself to appropriate these principles which he clearly and distinctly perceives to be true, then. But, as I intimated earlier, this gives rise to a natural objection. The objection is simply that he cannot then claim to be protecting his beliefs against any potential attack from a sceptic. Consider the sceptic who remains at the level of general reflection, where the Reflective Question arises, and who refuses to countenance any reliance on any clear and distinct perception until that question has been given some general answer. Descartes does have a general answer to the Reflective Question, but only because he has already allowed himself to rely on clear and distinct perceptions. (This is in effect the so-called Cartesian Circle.
²¹
) Does Descartes have a satisfactory reply to this objection?

No, not if a ‘satisfactory’ reply is a reply that will satisfy the sceptic.
²²
But it would be misleading simply to say, without further ado, that Descartes has therefore been defeated in his project by the sceptic. The person we are now calling ‘the sceptic’ declines to step down from the level of general reflection, in other words declines to give his full attention to anything, until he can be rationally persuaded to do so. But it is obvious that he cannot be rationally persuaded to do
anything
unless he gives his full attention to reasons that are put before him. Furthermore, we
already knew
that at that general level everything can be doubted. It was precisely Descartes’ strategy to begin at that level and to doubt everything. And ‘everything’ here includes his own existence, by the way. He did not find even that indubitable until he eventually turned his attention to the issue (
Meditations
, VII: 24–25). The person we are now calling ‘the sceptic’ is like one of those tiresome children who, through no desire to learn but simply in order to annoy, persists in asking ‘Why?’ every time an answer is given to one of his questions. (Here a quotation from William James is pertinent: ‘General scepticism is a permanent torpor of the will … and you can no more kill it off by logic than you can kill off obstinacy or practical joking’ (James (
1978
), pp. 273–274).
²³
) So, although we
could
say that Descartes has been defeated in his project by the sceptic, there is at least as much rationale for refusing to dignify this metaphysically uninteresting position with the label ‘scepticism’. And then the issue is what to make of the undeniably sturdy structure – by any reasonable standards of sturdiness – which Descartes has
built.

4. The Shape of Descartes’ System. Its Epistemology

This is a structure in which we, who make sense of things, do so by appeal to data which indicate how things, independently of our sense-making, are. And this applies in particular to our most general sense-making, that which we achieve when we successfully engage in metaphysics. We have seen that Descartes talks in terms of perception where metaphysical matters such as the scholastic principle about cause and effect are concerned. This is perception of a non-sensory kind. He also sometimes uses the word ‘intuition’ for it (see Rules, X: 368).
²⁴
Henceforth I shall do likewise. But the word ‘perception’ is entirely apposite. For intuition is in certain fundamental respects just like sensory perception. Whether we intuit that something is so, or sensorily perceive that something is so, there is a more or less metaphorical sense in which we ‘see’ how things are, and in each case this is something that we are able to do because we have the appropriate mental apparatus which supplies us with data about how things are.
²⁵

Sensory perception can have its own relative clarity and distinctness. Indeed it can be ‘sufficiently clear and distinct’ for its own purpose, which is to serve as a rough guide to what benefits us or harms us (
Meditations
, VII: 83). But it never has the clarity and distinctness of intuition. And there is not the same indubitability in the case of sensory perception as there is in the case of intuition. Nor should there be. For there is not the same reliability either. Sensory perception often inclines us to believe what is not true, for example when a square tower looks round from afar (
Meditations
, VII: 76). This has two important corollaries for Descartes’ overall system. First, Descartes insists that, in order to achieve insight even into the nature of physical objects, we must appeal ultimately to intuition rather than to sensory perception. The essence of a physical object, on Descartes’ view, is its sheer spatio-temporality, and this is something that is revealed to us by abstract mathematical reasoning from what we grasp in intuition (see
Meditations
, XII: 30–31; cf. also
Principles
, Pt One, §§23ff.).
²⁶
The second important corollary is Descartes’ account of error. He certainly needs an account. For he needs an explanation of how, despite God’s benevolence, we are not error-proof. Descartes’ explanation is that the fault when we err is entirely ours. We judge how things are even where our perceptions do not
have the requisite clarity and distinctness and where it is within our power to withhold our judgment. I see a square tower from a distance, say, and I jump to the conclusion that it is round. (See
Fourth Meditation
.) This does nothing to impugn the assurance that Descartes has given us that, when we do all that is within our power to avoid error, we shall avoid it.