PART THREE

APPLICATION OF THE CRITERION
TO DEMONSTRATE THE TRUTH
OF NON-PURE, OR MATERIATED KNOWLEDGE

CHAPTER 3

The certainty of perception,
especially of the perception of ourselves

1194. We must now discuss the importance of intellective perception. In this life we perceive only two kinds of real things: 1. ourselves; and 2. bodies. We begin with the certainty of the perception of ourselves.

1195. Myself is a being who thinks, and is therefore a substance. Myself as substance is a feeling, because myself feels, and always feels the same in all the actions it does. When it is not acting, it still feels because it is alive and essentially feels that it is alive.

1196. Myself is, therefore, a fundamental feeling because all its feelings are rooted in it.(128) It needs no other sensations; it is of itself. 'We' can never be without ourselves. All other sensations need our essential feeling because all possible sensations are simply modifications of ourselves.
With the feeling myself, therefore, we feel an ens, a substance, a subject (that is, a living, feeling principle). Consequently, if we think this feeling, we perceive a substance. There is therefore a substance which we perceive directly, and we are this substance.

1197. When we perceive ourselves with our understanding, we have no need of any intermediagment. Conscious of the fundamental feeling, we say to ourselves: 'We exist', meaning: 'It is us', that is, it is this feeling, which is a substance, an ens which subsists with an internal energy. In fact, in the feeling of myself the human being feels precisely the energy in which he is, the energy through which he is distinguished from all other existing substances.(129)

Because our particular subsistence is understood in the feeling ourself, our understanding, in order to perceive ourself, has only to turn its attention to ourself and acknowledge the real, subjective existence already present in the feeling. We do not need integration or induction to do this because the acknowledgement is carried out by means of the notion of objective being which is in the understanding.

1198. If the perception of myself were not granted, I could not ask whether it were certain. However, whether true or illusory, it is given by nature because composed of two primitive facts: 1. the form or idea of being; 2. the matter or fundamental feeling, perceived of itself and indicated by the monosyllable 'I'. Granted, therefore, that it is given, is the perception of myself true and certain?

The idea of existence, the first part of the perception, is verified per se, as I have shown earlier (cf. 1065 ss.).
We wish to verify whether the feeling given by nature (myself) which we judge to exist, is the judgment which constitutes the intellective perception of myself. We can therefore express the question, 'Is the perception of myself certain?', as follows: 'Does my understanding judge correctly when it applies the universal predicate of existence to my feeling?'

1199. The answer is contained in the general principle of the application of the form of reason (predicate) to the matter (subject), a principle discussed in the preceding chapter. We saw that every activity, every feeling, is simply an actuation, or a term of the actuation, of being. The predicate is therefore correctly applied to the feeling constituting myself, and because this perception of myself is the most direct, and also the condition of all other perceptions (of contingent things), it is the most certain.

1200. In his refutation of the Academicians, St. Augustine begins with the undeniable fact of the perception of myself [App., no. 7]. He argues:
In this (that is, in our judging that we are alive) we have no fear of being deceived by some likeness of truth, because even the person who is deceived is undoubtedly alive. Our seeing this cannot be impugned by the objections brought against external vision. Objections of this kind suggest that we are perhaps deceived in the same way that our eye is deceived when it sees a stick bent in water, or when sailors appear to see towers move, and an infinite number of other things which differ from the way they are seen. But the truth under discussion is not seen by the bodily eye; the knowledge by which we know that we live is much deeper. The Academician cannot say: 'Perhaps you are asleep, and without knowing it, you dream that you see.' Certainly the things we see in dreams resemble very closely what we see when awake; we all know that. But the certainty of our knowledge of being alive does not make us say: 'I know I am awake', but 'I know I am alive'. Whether we are asleep or awake, we are alive. Dreams cannot deceive us relative to this knowledge because both sleeping and seeing things in dreams is the act of one who is alive. Nor can the Academician attack such knowledge by saying: 'You're a raving lunatic, and don't know that you are.' Things seen by healthy people are very much like those seen by lunatics. A lunatic is alive! And in answer to the Academicians we do not say: 'I know I am not a lunatic', but: 'I know I am alive' Hence, people who say that they are alive can never be deceived or lie. Anyone who says: 'I know I am alive' may perhaps be accused of a thousand kinds of false visions, but that does not disturb him because anyone who is deceived is alive.(130)

1201. St. Augustine goes on to deduce many other truths from the unshakeable certainty of our being alive and of our being:
If such were the only things found in human knowledge, they would be very few. However, they multiply so much in every way that they are no longer few but reach an infinite number. The person who says: 'I know I am alive', says he knows one thing. But if he says: 'I know that I know I am alive', he says he knows two things. And to know that we know these two things is to know a third truth. In this way we could add the fourth, the fifth and innumerable other truths, if we were able. But because it is not possible to understand an indefinite number by adding one at a time, nor to go on stating numbers interminably, we at least certainly understand and say that the series is true and that it is so countless that we truly cannot understand and state its infinite number.

The same can be said of the certainty of our will. It is surely imprudent to reply 'Perhaps you are deceived?' to someone who says 'I want to be happy'. If the person says: 'I know what I want, and I know that I know it', a third affirmation that the person knows these two truths can be added. And then a fourth that they know that they know the two truths, and so on indefinitely.(131) Thus, if someone says: 'I do not want to make a mistake', whether he errs or not, it will always be true that he does not want to err. It would be the height of impudence to reply to such a person: 'Perhaps you are deceived'. Even if he were deceived, he is not deceived in wishing not to be deceived! And if he adds that he knows it, he can add as many such truths as he wishes, aware that the number of truths is infinite. The person who says: 'I do not wish to be deceived, and I know I do not wish to be deceived. I know that I know', can indicate, even if clumsily expressed, an infinite number of truths.
And other things can be found which firmly refute the Academicians, who maintain that the human being is unable to know
anything.(132)

1202. As a conclusion to this chapter, I observe that what is presented to our understanding cannot in any way be different from what we know. To be presented with something means we must feel it; it is the thing in so far as it is known and perceived by us. As felt, it must be identical to itself when known directly, that is, perceived intellectively. To perceive it is simply to know or affirm to ourselves that we feel it. Thus the intellective perception has the same identical term as the sensation, which is its proximate object. In this kind of knowledge, deformity or falsity cannot be present in anything of itself. This confirmation of intellective perception arises from the simplicity of the spirit, which, as a single principle, unites feeling and intellection.

(128) I demonstrated and explained this in vol. 2, 692 ss. Substantial feeling corresponds to what St. Augustine says in bk. 9 of his work on the Trinity: SUBSTANTIALITER notitia (sui) inest menti [Information about itself is SUBSTANTIALLY in our mind]. In fact, the soul, in order to perceive itself immediately, needs only to turn its attention to its own feeling. However, this action of turning our intellective attention to our own feeling is not innate. Hence St. Thomas says that the mind has only an habitual notion of itself necessarily and substantially: Notitia qua anima se ipsam novit, non est in genere accidentis, quantum ad id quo HABITUALITER cognoscitur, sed solum quantum ad actum cognitionis [The information with which the soul knows itself is not classified as an accident relative to that by which it is HABITUALLY known, but only relative to the act of knowledge] (De Verit., 10, 8).

(129) Nevertheless, when we analyse the perception of ourselves (and of all other subsistent things), we find that pure being is a different activity from feeling. Hence, we who are a feeling have being, not from ourselves but from elsewhere. Thus, the expression used by some German and French philosophers, 'We exist through ourselves', is incorrect. Indeed, our observation clearly makes true the opinion of St. Augustine and other Fathers that creatures, absolutely speaking, are not.

(130) De Trinitate, bk. 15, c. 12.

(131) We must not think that St. Augustine's observation is a clever but vain subtlety, and that these truths he speaks of are differences only in words and not in reality. Anyone who understands will surely find the observation very acute and helpful in knowing the nature of human cognitions. St. Augustine distinguishes the different reflections our mind carries out on its own cognitions. He notes that every reflection is a new act of the mind, differing from the preceding reflection and producing some new knowledge. It is of the greatest importance to recognise this, particularly when it is applied to explain facts of the mind. In this work I have frequently been obliged to make use of the distinction between reflective and direct knowledge, demonstrating that they are not the same. They are entirely distinct and sometimes contradict each other (cf, amongst other places, 1149-1157). A reflection on the knowledge we have, that is, knowing that we know, so increases our knowledge that the new knowledge relates to the former in the way that more relates to less, or even the infinite to the finite. With reflective knowledge we rule and control direct knowledge as we will; only reflective knowledge brings direct knowledge under our free will. We would never have discovered the art of writing if we had not reflected on language. Numbers are an invention arising from the reflection on the ideas of numbers. Algebraic letters are the result of a reflection on numbers. Analytical functions arose from a third reflection on algebraic letters. This is the real meaning of the apparent play on words: 'We know that we know that we know'! It is the simplest formula expressing the order of ideas, to which the Analytical Functions of Lagrange belong.

(132) De Trinit., bk. 15, c. 12.