Patterson, Sarah (2007). Clear and distinct perception. In Janet Broughton & John Carriero, A Companion to Descartes. Wiley-Blackwell. pp. 216-234.
Clear and distinct perception occupies a central place in Descartes’s philosophy. His most famous work, the Meditations, is designed to teach his readers how to perceive clearly and distinctly.
He wrote to Mersenne that “we have to form distinct ideas of the things we want to judge about, and this is what most people fail to do and what I have mainly tried to teach by my Meditations” (3:165; AT 3:272).
We learn in the Fourth Meditation that everything we clearly and distinctly perceive is true: “if, whenever I have to make a judgment, I restrain my will so that it extends to what the intellect clearly and distinctly reveals, and no further, then it is quite impossible for me to go wrong” (2:43; AT 7:62). We are assured of this by our knowledge that we are created by a perfect God; since our clear and distinct perceptions are real things, they must come from God, and so cannot be false (1:130; AT 6:38, 2:43; AT 7:62, 1:203; AT 8A:16).
① Descartes’s appeal to God’s perfection to guarantee the truth of clear and distinct perceptions gives rise to a familiar charge of circularity.
② But there is another familiar charge brought against Descartes’s appeal to clarity and distinctness as a criterion of truth: that he does not provide an adequate criterion of clarity and distinctness. This charge was famously made by Leibniz, who demanded a criterion for clarity and dis tinctness that was “palpable” and “mechanical” (cited by Gewirth 1943). It was put to Descartes himself by Gassendi in his objections to the Meditations: “please note, distin guished Sir, that the diffi culty does not seem to be about whether we must clearly and distinctly understand something if we are to avoid error, but about what possible skill or method will permit us to discover that our understanding is so clear and distinct as to be true and to make it impossible that we should be mistaken” (2:221; AT 7:318; see also 2:194–5; AT 7:279).
Descartes does offer a defi nition in the Principles of Philosophy, where he states that a perception is clear when it is present and open to the attentive mind, and distinct when it is not only clear, but so sharply separated from other perceptions that it contains only what is clear (1:207–8; AT 8A:22).
But without some elaboration of the crucial terms in the defi nition, it is hard to see how to use it to identify genuinely clear and distinct perceptions.
Ideas and Perceptions
Descartes distinguishes two senses of the word “idea” in the Preface to the Meditations. He writes that “idea” can “be taken materially, as an operation of the intellect,” or “it can be taken objectively, as the thing represented by that operation” (2:7; AT 7:8).
Ideas in the objective sense are not described as the objects of the acts or perceptions which are ideas in the first sense, contrary to the reading given by Kenny (1967: 229).
Rather, ideas taken objec tively are the things represented by the acts or operations which are ideas taken materi ally. This entails that ideas as acts, i.e., as thoughts or perceptions, are themselves representational. This is not surprising, since for Descartes all thoughts are represen tational, in the sense that they are directed on objects. But how can ideas in the objec tive sense be the things represented by thoughts? This suggests that we only ever think about ideas, which is indeed Kenny’s interpretation of Descartes’s view (Kenny 1967: 242). But we can avoid this interpretation if we attend to the model of thought Descartes employs here.
In the First Replies Descartes explains that an idea is “the thing which is thought of insofar as it has objective being in the intellect” (2:75; AT 7:102). The thing which is thought of existing objectively in the intellect is the thing represented by the thought. A thing x becomes an object of thought, something represented by an act of the intellect, when it exists objectively in the intellect by way of an idea.
Where there is an idea taken materially, an act of thought representing or directed on some object x, there is an idea taken objectively, an object x to which the thought is directed. The idea of x taken materially as an act of thought directed on x is constituted by x existing objectively (as an object of thought) in the intellect.
This is borne out by Descartes’s example: “the idea of the sun is the sun itself existing in the intellect – not of course formally existing, as it does in the heavens, but objectively existing, i.e., in the way in which objects normally are in the intellect” (2:75; AT 7:102; emphasis added). So the idea of the sun taken materially is simply a thought of the sun, and the idea of the sun taken objectively is the thing represented by that thought, the sun, existing as an object of thought in the intellect. Arnauld describes the dual material and objective character of Cartesian ideas thus: “I take perception and idea to be one and the same. Nonetheless . . . this thing, although single, stands in two relations: one to the soul which it modifi es, the other to the thing perceived . . . and the word ‘perception’ more directly indicates the fi rst relation; the word ‘idea’, the latter relation” (Arnauld 1775: 198, quoted by Nadler 1989: 167).
Some Accounts of Clear and Distinct Perception
The best-known account of Cartesian clarity and distinctness is probably that provided by Gewirth (1943).
The core of Gewirth’s interpretation is the notion that an idea of x is minimally clear if it contains the property which constitutes the nature and essence of x, and minimally distinct if it contains nothing contradictory to the essence of x. A minimally clear and distinct idea of x becomes clearer if more attributes necessarily connected with the nature of x are included in it. The idea thereby also becomes more distinct, since “the richer its content, the more is it distinguished from what is other than it” (Gewirth 1943: 90).
This allows for an idea to be clear yet confused, if it contains what constitutes the nature of its object as well as something contradictory to that nature (see Gewirth 1943: 87, fn. 34). This is the case with the idea of pain in a body part, which Descartes gives as an example of an idea that is clear but confused; it contains the feeling of pain, which is a mode of thought, but confuses it with the idea of something resembling the feeling existing in a part of the extended body.
The notion that having a clear and distinct idea of x involves understanding what does and does not belong to the nature of x fi gures in other interpretations besides that of Gewirth. For example, Curley remarks that “having a clear and distinct idea of a thing . . . is a matter of seeing what is and what is not involved in being that thing or a thing of that kind” (Curley 1986: 169–70); more specifically, he proposes that “having a clear and distinct idea of a thing, or of a kind of thing . . . is a matter of recognizing that there are certain properties we cannot but ascribe to a thing of that kind (clarity) and others which we are not at all compelled to ascribe to it (distinctness)” (ibid.). Similarly, Smith claims that an idea of x is clear just in case it exhibits the element or elements that constitute the nature of x, plus the relation that unifies them, if x is complex (Smith 2001: 294).
Obscurity, Confusion, and Prejudice
So where there is a prejudice, there is an obscure and confused idea, and the prevalence of prejudice bears witness to the prevalence of obscure and confused perception. But Descartes believes that our predicament is even worse than this would suggest.
Our longstanding habit of assent to prejudices produces the false belief (itself a prejudice) that they are based on clear and distinct perception.
Mistaking obscure and confused percep tions for clear and distinct ones is not a mistake to which we become vulnerable only once we have read the Meditations, and have been introduced to Descartes’s concept of clear and distinct perception. Thanks to our prejudices, it is a mistake we make already: “there are few who correctly distinguish between what they in fact [distinctly] perceive and what they think they [distinctly] perceive, for few are accustomed to clear and distinct perceptions” (2:348; AT 7:511).
Not only are we unaccustomed to genuinely clear and distinct perceptions, we are so accustomed to obscure and confused perceptions that we take them for the genuine article. Descartes thinks that “most people have nothing but confused perceptions throughout their entire lives” (1:220; AT 8A:37). But the habit of assent to these confused perceptions is so familiar that we take them for clear ones, and thus “we make the mistake of thinking that we clearly perceive what we do not perceive at all” (1:218; AT 8A:35).
Clear and Distinct Perception in the Second Meditation
What is involved in paying closer attention to what the wax, or the mind, consists in? In each case, the meditator fi rst discovers that certain properties thought to pertain to the nature of the thing in question do not in fact do so (we might call this the eliminative phase). She then discovers that certain properties not yet recognized as pertaining to its nature do in fact do so (we might call this the ampliative phase). The eliminative phase yields a conception which reveals what constitutes the thing’s nature (thinking, being extended), while the ampliative phase expands this concep tion by exploring what belongs to such a nature (various modes of thought, innu merable ways of being extended). The meditator fi rst homes in on the essence of the thing, excluding what does not belong to it, and then draws out what does belong to it.
The Nature of Clear and Distinct Perception
In the Meditations, “clear” and “distinct” seem to be used as correlatives, as are “obscure” and “confused.” But the defi nitions provided in the Principles entail that a perception can be both clear and confused, though it cannot be distinct unless it is clear.
A perception is said to be clear when it is “present and open [praesens et aperta] to the attending mind – just as we say that we see things clearly when, being present to the regarding eye, they move it suffi ciently strongly and openly” (1:207; AT 8A:22).
A distinct perception is one that is not only clear, but “so sharply separated from every thing else that it plainly contains nothing but what is clear” (1:208; AT 8A:22).
However, to say that nothing in a distinct perception of x is hidden or concealed is not to say that the perception reveals all there is to know about x. To say that would be to erase a distinction on which Descartes insists, the distinction between distinct and adequate perception. Adequate knowledge, and presumably adequate perception, “must contain absolutely all the properties which are in the thing which is the object of knowledge” (2:155; AT 7:220). Descartes holds that a created intellect may have adequate knowledge of many things, but cannot know that it has such knowledge unless God grants it special revelation of that fact (2:155; AT 7:220). Since divine revelation is not needed in order to know that one has a clear and distinct perception, an idea of x need not contain all the properties of x in order to be clear and distinct.
Questions About Sensory Ideas
But there are two different ways in which God might have achieved this, and so two possible interpretations of the nature of clear and distinct perception.
According to the fi rst, clear and distinct perception is a phenomenally distinctive experience, a kind of feeling that compels the will to assent. God has molded our minds so that we have this experience only when we perceive contents that are true, and thus we are only compelled to assent to truths.
According to the second, clear and distinct perception is the perception of a content that we fi nd self-evidently true, and God molds our minds so that we fi nd true contents self-evidently true. These views of clear and distinct perception might be described as phenomenal and inten tional, respectively.
On the intentional view, clarity and distinctness are a feature of the content perceived, while on the phenomenal view they are a feature of the perceiv ing of it.
On the phenomenal view, the compulsion to assent to what is clearly and distinctly perceived is a form of brute compulsion, while on the intentional view it is a form of rational compulsion.
The phenomenal view accords with a popular reading of Descartes’s conception of the mind, one that David Chalmers expresses when he says that “with his notorious doctrine that the mind is transparent to itself, [Descartes] came close to identifying the mental with the phenomenal” (Chalmers 1996: 12). On this view, recognizing genuine clear and distinct perceptions is a matter of recognizing a distinctive phenomenal feel, one that is known by being experienced rather than by being described. This accords with Descartes’s claim that the method of identifying such perceptions is better learned from examples than by rules, and it might be thought to account for the uninformativeness of his one attempt at explicit defi nition. If what it is like to perceive clearly and distinctly can only be identifi ed ostensively as that type of experience that makes doubt impossible, no wonder Descartes does little better than compare it to a pain.