PART TWO

APPLICATION OF THE CRITERION TO DEMONSTRATE
THE TRUTH OF PURE KNOWLEDGE

CHAPTER 2

Truth, or the idea of being,
as the means of knowing all other things(59)

1112. So far I have considered the idea of being in itself, and have shown that it is an intuition immune from all sceptical doubt. I must now show how the total certainty of things rests upon this solid base of the intellectual world.
We must therefore consider the idea of being in its application to things.
We shall begin by considering its aptitude for application. And because the title ‘truth’ depends upon this aptitude, we shall make ‘truth’ the subject of this chapter.

1113. Individual authors, in giving various meanings to a word, may be guilty of improper use of language. The same cannot be said when different meanings depend upon mankind’s use of a word. There would seem to be no impropriety here. Rather, there will be something common to all the different meanings. This common notion, found in all the various senses of the word, will be its most general meaning and the unique essence of whatever the word signifies. If we examine the different meanings normally given by common parlance to the word ‘truth’, we can see that its most extensive meaning, its general notion, and the unique essence properly indicated by it, is that of exemplar. I have therefore defined truth as the exemplar of things.(60)

1114. The concept of exemplar includes a relationship with what is drawn from the exemplar, that is, with its copy. The copy is ‘true’ when it is perfectly like its exemplar. Hence, we must distinguish between truth and true things: truth is the exemplar; things are true when they conform to their exemplar, that is, when they share in truth.

1115. We also speak of ‘the truth of a thing’, and mean the likeness of the thing with its exemplar. We use this meaning because the likeness of the thing with its exemplar is its truth; through this truth, the thing is true and shares in the content of the exemplar from which it has been drawn.

To possess a clear concept of truth, therefore, we must first have in our mind an exact, clear concept of likeness. How superficial the mind of those philosophers who supposed that the likeness of things could easily be understood, and at the same time supposed that it was very difficult to indicate the origin of universal concepts, particularly of the truth of things (vol. 1, 180–187)! On the contrary, likeness is the only concept by which we understand how things are true or false. We must therefore examine this concept a little, profiting from what I have already established regarding the nature of the likeness of things.

1116. Any object whatsoever, even external, can be considered as an exemplar, provided we consider it in its relationship as norm or type of other beings which must be formed according to it and like it.
In this sense, we say that the whole of nature is an exemplar for the artist, who copies and portrays its different parts. The events of human society and patterns of behaviour are an exemplar for the tragic or comic poet. A book transposed into another language can be correctly called ‘exemplar’ relative to the translation, which must agree perfectly with the original text.

Hence, nature is the truth of works by artists who have imitated and copied her. So we say: ‘This is a true portrait’, ‘There is much truth in this picture’. In the same way we say a tragic or comic scene fully presents the truth, if it resembles what happens in fact. St. Jerome, using a similar propriety of speech, says that having kept his translation in line with the Hebrew text, he has rendered it according to the Hebrew truth.(61)

1117. We must now turn our attention to an important observation.

I have shown elsewhere that external things, in so far as they exist outside our mind, cannot be compared with one another; each stands by itself. Their likeness or unlikeness is simply a relationship they have with the mind that perceives them.(62) This relationship consists in our perception of many real entia by means of one single idea or species. Thus, their likeness can be defined as: ‘Their aptitude for being thought by an intelligent mind by means of one single species’(63) (we are speaking solely of the part in which they are similar). For example, a carpenter does not compare two planks of wood simply by the external act of placing them side be side to see if they have the same size and shape. He compares them by the internal act of his mind at the moment they are side by side — the external, sensible conjunction of the planks is only an aid to the comparison.

When I compare a beautifully painted landscape with the panorama it depicts, and find that the painting possesses perfect truth, I am not comparing it with anything outside me — I cannot insert the painting into nature itself and make it one with nature, or even place the painting and nature side by side, as the carpenter does with the two planks. However, although I cannot compare nature with the painting I see and admire, because nature exists in itself outside me and unperceived by me, I can nevertheless compare it with the idea and images I have of nature, or at least with nature in the way I think it. This is so true that I can carry out the comparison even in total darkness when no natural panorama is sensed before me, or even in a place where I see only a strange, ugly nature, totally different from the idyll of the painting with its gentle hills and rich plains in brilliant sunshine. Comparison therefore is always a function of my thought which, although simple, can compare many perceptions with a single species, noting where the perceptions form a single species, and where the species themselves are multiplied. The same argument can be put forward about any external thing whatsoever used as an exemplar: in order to be called ‘exemplar’, it must always be present in the mind; in short, it must be an idea.

An exemplar therefore is simply an idea, often accompanied by its image, because only a mental conception can serve as an exemplar.(64)

1118. This observation allows us to perfect the definition we have given of truth and reduce it to this simple form: ‘Truth is an idea in so far as an idea is an exemplar of things.’(65)

1119. There are as many truths as there are exemplar-ideas of things. This is the only sense in which the word ‘truth’ is used in the plural, as for example, when we say: ‘Truths are diminished among the children of men’,(66) or we speak of a special truth: ‘This is an important truth’, or when Dante says:

1120. Per se, the exemplar-ideas of things correspond in number to the full specific ideas (cf. vol. 2, 646–656) which allow us to know things positively and fully. But relative to ourselves we can say that there are as many exemplar-ideas as the fullest ideas we can have of each thing.(68) This explains why we say that each thing has its truth in its species. The masters teach that ‘where several things are true, there are several truths, but in the case of one thing there is only one truth’.(69) In the same way we must affirm that all the individual things belonging to an idea have a single truth because, as we have said, they have a single exemplar, a single idea that represents them perfectly and makes them known (cf. vol. 2, 501 ss.).

1121. All these truths are specific or generic(70) and as such refer to the class of things that each truth determines and forms with its own unity.(71)
‘Truth’ is also used in ordinary language with an absolute sense, and always in the singular. The sceptics themselves give it this meaning when they say: ‘Truth cannot be known, or does not exist’, or something similar. But what sense has mankind given to the word when it is used in this way?

A specific idea is an exemplar of, and limited to a class of entia it represents or makes known to us; individuals of the same species have a determined mode and degree of being which limits and specifies them. But things, whatever their species, have something in which they are equal. This element is being itself (prescinding from its modes and degrees), because they all are. The idea of being therefore is that which represents all entia of any species whatever, and by which all entia are known. It is the idea to which all species are reduced, and could for this reason be called the species of species.(72)
The idea of being also differs from all species and genera in that all species and genera are this same idea, but with limitations.

Hence, if every species and genus of things has its particular exemplar, that is, its truth in the specific or generic idea, and if above this exemplar there is another idea, which is the exemplar and therefore the truth of all possible species, and if finally this idea is the idea of pure being, then the idea of being is the truth of all things.

The idea of being therefore can be called ‘truth’ when it is considered as the exemplar of things in so far as they are known by us, as I have said elsewhere.
Hence, the idea of being is the one, universal, absolute truth by which we know all things, because it is the universal exemplar, and expresses that in which all things are equal.

1122. St. Augustine gave truth this absolute sense when he defined it as: ‘That which indicates being.’ He is speaking therefore of the idea of being, because this idea makes known and indicates what is. Veritas est qua ostenditur id quod est [Truth is that which manifests what is].(73) St. Hilary’s definition has the same sense: Verum est declarativum, aut manifestativum esse [Truth is being in so far as being indicates and manifests],(74) that is, being considered as that which declares and manifests things. This is being that we intuit, being as it is in our mind — in a word, the idea of being. When St. Anselm said: ‘Truth is related to all true things as time is related to all temporal things,’(75) he was speaking about the one, absolute truth, about the ‘incorporeal light in which, as St. Augustine says, the mind sees everything it knows.’(76)

1123. Knowledge results from sharing in truth. It will be sufficient, therefore, to investigate the means by and in which we know things in order to have found truth.

The following extract contains the teaching of the author of the Itinerary on this point:

The action of the intellective power lies in the intellect’s perception of terms, propositions and conclusion. The intellect understands the meaning of terms only when it comprehends what each thing is by means of the thing’s definition. But no definition can be given without the use of higher notions, which in turn are obtained by means of still higher notions, and so on until we reach the highest and most general notions. If we do not know these supreme notions, the inferior notions cannot be definitively understood. Hence, we have to know what ENS is in itself in order to know fully the definition of any particular substance.(77)

According to this great man, therefore, all knowledge is ultimately resolved in the knowledge of ens in itself. In other words, through the knowledge of ens we know everything else. Consequently, the idea of being, as the means by which we know things, is truth.

Let us now turn to St. Thomas, another luminary of Italy and of the Catholic Church. He says:

1124. St. Thomas continues by showing that truth is the cause of knowledge:

All knowledge is accomplished by an assimilation(82) of the knower(83) to the thing known, in such a way that the assimilation is called cause of the knowledge… The first comparison of ens to the intellect, therefore, requires that ens should correspond to the intellect. This correspondence is the proportion between the thing and the intellect,(84) and in this correspondence the concept of true is formally accomplished.(85) This conformity or proportion between the thing and the intellect, therefore, is what is added by the meaning of the word true to the meaning of the word ens. And, as we have said, knowledge of the thing depends upon this conformity. Hence, the entity of the thing’ (being in itself) precedes the concept of truth, but KNOWLEDGE(86) IS AN EFFECT OF TRUTH.(87)

1125. A concept expressed in new language is easily taken for a new concept. This explains the great number of apparent objections to truth on the part of sceptics and many sceptical sects. If, however, we carefully examine the concept of scepticism, we see that it and its philosophy are only one, just as truth itself, which the sceptics attack or at least think they are attacking, is one.
In order to counter this error or travesty of the mind and this pathetic display of imagination, we must show what scepticism is in itself, without any of its trappings, and reduce it to its ultimate expression.

1126. Scepticism has appeared under four principal forms:

1.Some sceptics say that truth does not exist.
2.Some limit themselves to saying that truth cannot be known.
3.Some say that only a truth relative to us, a subjective truth, is known. And finally
4.Some assert nothing but say they are doubtful about everything, even about the existence of truth.

1127. The third of these forms maintains simply a subjective truth. But subjective truth is not truth; this is a misuse of the word, and the misuse of a word cannot summarise a system.
To grant knowledge of a subjective truth means not granting knowledge of any truth. Consequently, the third system, in which the question is discussed only apparently and by misusing words, must be reduced to one of the first two. We have to be ready therefore either to deny human beings knowledge of truth (the second form), or go further and deny the existence of truth (the first form) [App., no. 4].

1128. However, the first and second systems differ only in expression, not in reality.
If I say I have not the slightest knowledge of truth, I cannot affirm its existence, precisely because I know nothing about it. The second system, therefore, ultimately leaves the existence of truth in doubt, affirming only that its existence cannot be known.

The first system comes to mean the same: anyone affirming that truth does not exist, affirms that he does not know truth. But if he has not the slightest knowledge of truth, he cannot deny it. This system also must be reduced to affirming that truth is not known while leaving its existence in doubt.

1129. This system, composed of an affirmation and a doubt, was easy to refute because of the contradiction in its terms. Thus, we find in antiquity an unanswerable refutation of such an absurd system. For example, we read in Lucretius:

This ancient confutation of the sceptics is irrefutable. We can only wonder why scepticism continues to reappear, until we remember that it is not a philosophy but a disease, a frenzy enslaving humanity.

1130. In fact, the formula, ‘Truth cannot be known’ (to which we have reduced scepticism), cannot be emended in any way whatsoever. It must be eliminated. No matter how it is expressed or modified, it remains essentially absurd and contradictory, as I shall now explain.

Let us change the formula to another well-known form: ‘The only truth that can be known is that truth cannot be known.’

The truth exempted by scepticism is: ‘Truth cannot be known.’ But, if some truth can be known, it is false that, absolutely speaking, truth cannot be known. The truth exempted by scepticism is itself, therefore, a false proposition. For the exempt proposition to be true, it must contain the exception by which alone scepticism affirms the proposition to be true. But if the exception itself must be contained in the exempt proposition, we have a formula incapable of completion, since it would continue ad infinitum. For example: ‘No truth can be known except this truth that "No truth can be known except this truth" that "No truth can be known except this truth"’, and so on ad infinitum. Because we would never reach the end, scepticism’s formula is intrinsically impossible; if the formula cannot be stated, neither can it be thought. By force of its own system scepticism is condemned to pronounce its formula for the duration of its life, a formula that has meaning only when finally completed. But like any endless formula, it can never be finally pronounced. Thus, scepticism, unable to formulate its thought but eternally engaged in doing so, is in a state in which it can no longer think, because no thought can be expressed until it is completed.

1131. This observation had been made, and ancient scepticism had collapsed, when Pyrrho emerged and connived a more refined form of scepticism, the scepticism of doubt.(89) He said he neither denied nor affirmed anything, but doubted everything. He thought he had thus avoided the contradiction directed against the sceptics who preceded him. This form of doubt is the only apparent form that scepticism can have. We must therefore discuss it.

1132. The sophisticated sceptic desires to avoid at all costs the contradiction found among cruder sceptics who resolutely affirm their denial of the possibility of any affirmation whatsoever. He knows he must avoid every contradiction, honing his mind to keep scepticism in fashion and present it as a system without any intrinsic contradiction. Hence he recognises at least the principle of contradiction and presupposes some sure truth within the system of doubt. It was in fact this sure truth which guided our sceptic in forming his system. His sole desire that the system of doubt should be free of all contradiction led him into contradiction from the beginning!

1133. Let us accept that these convolutions and knots with which scepticism strangles itself to death are silken threads keeping it alive and topical. This kind of scepticism does not affirm that truth cannot be known, because it sees the contradiction in such an affirmation. However, if the doubt must not contain an affirmation, such a system of scepticism will end by eating its own words.

When sceptics of this kind say ‘I doubt’, they have pronounced an affirmation, because they have affirmed that they doubt. But if every affirmation is to be excluded from their doubt, they must doubt their doubt, and say ‘I doubt that I doubt’. In which case, they must go back another step and make their doubt fall on the very doubt about the doubt; they will doubt whether they doubted their doubt. The formula has now added another link and become: ‘I doubt whether I doubt that I doubt.’ But this is no better; the proposition still affirms, at least with the third verb if not with the first and second.

The sceptics must surely see how difficult it is to exclude every affirmation from their doubt. If now they add a further link, the formula becomes: ‘I doubt whether I doubt that I doubt my doubt,’ which is certainly more sceptical but still an affirmation — the difficulty has been pushed back one step, not solved. In short, the difficulty remains as long as we apply this scepticism to an infinite series of doubt-links in which the final term, even if it were reached, would still be an affirmation. All we can say, therefore, is that the formula proper to this kind of scepticism must be an endless series. It would no longer be scepticism if the formula were to come to an end. The result must be a series of doubts of the following form: ‘I doubt that I doubt that I doubt that I doubt’ etc, ad infinitum.

Such a formula affirms nothing because we can never pronounce the completed formula, never find the final term. If the final term were found, the formula would end, which is contrary to the hypothesis. The affirmation, therefore, pronounced at the start of the formula, can never be completed, and we are left with a suspended affirmation. And a suspended affirmation means a suspended thought, because to think is to affirm.

We see from this formula that the theme of the sceptic’s teaching could alone fill every book on earth. When no more books are left, it must add an ‘etcetera’ because its extraordinary fecundity never comes, nor can come to an end. Young students who enter the school of the sceptics can be certain that for the whole of their life they will never hear completely even the simple title of the sublime philosophy they desire to know [App., no. 5].

If some divinity came down on this earth to judge the different schools of philosophy, something very strange would happen to the sceptics. The first question asked of the assembled philosophers would be: ‘What is your opinion?’ After hearing the statements of the other schools and rightly judging them according to their merit, our divinity would finally come to the sceptics. Each, in reply to his question, ‘What is your opinion?’, would begin to recite the one, real form of their system: ‘I doubt that I doubt…’ And each would continue for all eternity, crazily pursuing the infinite series of doubts to the scorn of the divine judge and of their fellow-creatures. Would that such scorn were the only punishment meted out to them!

1134. When scepticism is thus taken to its ultimate and inevitable expression, it renders all thought impossible, unless it accepts defeat by affirming truth.(90)
Scepticism accepts only one thought, and this cannot be activated.

1135. Granted what has been said so far, I can demonstrate this as follows.

I first discussed the idea of being (cf. 1065 ss.), and then truth (cf. 1112 ss.). I started from each concept and ended at precisely the same place, although by seemingly different routes.
Discussing the idea of being, I found that it constitutes the possibility of thought (cf. 1090 ss.), and that sceptics who deny being have rendered thought impossible, and thus contradicted themselves with the first thought they presumed to make.
In the case of truth, I found that sceptics who deny it are reduced finally to the same result: they render thought impossible (cf. 1134).

Consequently, to deny truth is to render thought impossible. To render thought impossible is to deny the idea of being. The idea of being is, therefore, truth. And this is what I proposed to demonstrate in this Article.

(59) We naturally see being, but in order to know that this being is the light which makes us know all things, that is, truth, we have to turn our attention to being itself and, after much reflection, come to know its extraordinary property and relationship with all things, by which it makes them known and evident. Only when we have obtained this knowledge, can we say we know the truth shining in us. We conceive being therefore with a direct, natural act, but under its relationship with truth we conceive it only by an act of reflection, which does not come about until long after the former conception. St. Thomas notes perceptively that ‘because ens falls within the concept of truth, but not vice versa, we cannot apprehend truth without apprehending the concept of ens. He continues: ‘Similarly when we compare what is intelligible with ens: ens can be understood only because it is intelligible. However, ens can be understood without reflecting on its intelligibility. In the same way, ens as understood is truth. But it does not follow, that when we understand ens, we understand truth’ (S.T., I, q. 16, art. 3, ad 3).

(60) Cf. Saggio sull’Idillio e sulla nuova letteratura italiana (Opusc. Filos., vol. 1, pp. 321 ss.). This meaning of the word ‘truth’ is clearly present in the writings of some authors; for example, in the following passage of Cicero: ‘Truth overrides imitation in everything’ (De Orat., 3, 57). Here, imitation is the opposite of truth; copy, the opposite of original or exemplar.

(61) Cf. in his Proemium: Quamquam mihi omnino conscius non sim, mutasse me quidpiam de hebraica veritate [Although I am not at all conscious of having changed anything of the Hebrew truth]; in the letter to Paulinus: Quamquam iuxta hebraicam veritatem utrumque de eruditis possit intelligi [Although both learned interpretations can be understood according to the Hebrew text].

(62) In order to understand this very important truth, the reader should recall what was said in volume 1 (cf. the footnote to paragraph 107, and paragraphs 180–187).

(63) The reply to the question: ‘How can a single idea produce knowledge of many things?’, is: ‘By adding to it the judgment about the subsistence of the thing.’ This judgment is referred to each thing in particular, and therefore individualises, as it were, the species. An act with which a word is pronounced internally can always be reduced to this formula: ‘The thing I am thinking with my present idea subsists,’ and ‘subsists so many times’ (this is the number of individuals) (cf. vol. 2, 402 ss.). Because the judgment is stimulated by sensations (vol. 2, 528 ss.), we can have many intellective perceptions based on one single idea. These perceptions are distinguished among themselves by different acts of judgment, all made with one idea and determined by sensations, as I have said.

(64) I have noted (cf. vol. 2, 648 ss.) that any contingent thing whatsoever can be thought in a more or less imperfect state. If I compare the ideas I have of something in a state of perfection and a state of imperfection, the sole difference I see is that the idea I have of the imperfect thing is the same as the idea of the perfect thing, but lacking some quality. In so far as both these ideas have something positive, they are one idea, not two. I use the idea of the thing considered in its perfect state in order to think the thing in all its possible states; I find everything positive in the perfect idea, and in order to think the thing imperfect, I need only subtract some part of what I am thinking. The name ‘exemplar’, therefore, should be used principally of the idea of the thing in its most perfect state. However, when we have not succeeded in forming the type of perfection, our exemplar is the most perfect idea we can have of things we know — in the arts the ability to form this near-perfect idea is found only in the most consummate artists. Furthermore, the degree of perfection of our taste and the degree of accuracy of our judgments about works of art depend on the degree of perfection of the exemplar which we have formed to guide our judgment. Properly speaking truth is this exemplar, in so far as it contains the total perfection of things. We are now in a position to understand the definition of truth given by Avicenna: ‘The truth of a thing is that property of its being which is permanent to the thing’ (Metaphys., bk. 11, c. 2).

(65) St. Thomas notes that truth properly speaking is in the intellect, and less properly in things, just as we say a medicine is healthy, although health strictly speaking is only in the animal (cf. De Verit., q. 1, art. 4). My own teaching, confirmed by this observation of St. Thomas, was first taught openly by St. Augustine. We have seen that the essence of anything is that which is thought in the idea of the thing (cf. vol. 2, 648). St. Augustine teaches that the essence of anything is precisely the truth of the thing: Veritas non est proprium essentiae: quia si sic, qua ratione dicitur: veritas est proprietas essentiae, posset dici e conservo, CUM OMNINO IDEM SINT [Truth is not something proper to essence. If it were, the same reason for saying that it is a property of essence could be used in a contrary sense, although THEY ARE ENTIRELY THE SAME THING] (Solit., bk. 2, c. 5).

(66) Ps. 11.

(67) Par. 3.

(68) The perfect exemplar of things is per se the full specific and absolute idea. But we cannot possess this exemplar or archetype. The exemplar or rule we must use for judging the truth of things and propositions is the best specific or generic idea we have. If the only idea we have is a negative generic idea, with which we think merely a nominal essence, we have to use it alone, and judge things relative to it because we have no better idea of them. However, all our imperfect ideas are always true and a part of the most perfect idea (truth or supreme exemplar and rule of things), as we have said (cf. vol. 2, 648 ss.). The extent of our faculty to judge what is true or false, therefore, depends on how much of the most perfect exemplar is present in the norm we use for judging.

(69) St. Thomas, De Verit., q. 1, art. 4.

(70) In themselves, truths of finite things are always specific. However, a generic idea, if it is the only idea we have of something, takes the place of truth for us, and becomes the exemplar according to which, for lack of anything better, we judge. In such a case, our judgments, in order to be accurate, must fall within the sphere of what we know generically; they are valueless for specific characteristics whose exemplar or rule for judging is lacking.

(71) We should carefully distinguish the three meanings of the expression, ‘the truth of a thing’. It can mean the exemplar-idea of the thing; this is the proper, natural sense of the expression. It can also mean ‘the truth contained in the thing’. In this sense, ‘the truth of a thing’ means exactly the same as ‘true thing’, and expresses the perfect correspondence between the thing and its exemplar; in other words, between its idea and its truth. Finally, if the true thing is either considered or is in fact an exemplar, the expression, ‘the truth of this thing’, corresponds exactly to ‘this truth’. Thus, in the following passage of Boccaccio: ‘No one attained the truth of the fact’ (Gior., 8, p. 4), the fact is taken as the exemplar, the truth itself, and means: no one was able to discover or know the truth, that is, this fact.

(72) The thought of being can be found in two modes: either imperfect, when we have only a simple notion of being (this mode is innate); or perfect, when all the properties consequent on the notion of being would also be known. We do not have the second mode. This distinction will be clarified later under The Forces Present in a priori Reasoning.

(73) De vera Relig., c. 36.

(74) Bk. 5, De Trinit.

(75) De Verit., c. 14.

(76) De Trinit., 12, c. 15.

(77) Operatio autem virtutis intellectivae est in perceptione intellectus terminorum, propositionum et illationum. Capit autem intellectus terminorum significata, cum comprehendit quid est unumquodque per definitionem. Sed definitio habet fieri per superiora, et illa per superiora definiri habent, usquequo veniatur ad suprema et generalissima, quibus ignoratis, non possunt intelligi definitive inferiora. Nisi igitur cognoscatur quid est ENS per se, non potest plene sciri definitio alicuius specialis substantiae (Itiner. mentis in Deum, c. 3).

(78) I think it helpful here to amass references to important authorities, which enables us to see how this important, basic truth of philosophy was generally known by the most observant, lucid thinkers. Note, for example, that the same observation is found in Avicenna (Metaphysics, bk. 1, c. 9), whom St. Thomas cites here in confirmation of his own opinion.

(79) What is not being is nothing, and cannot in itself form the object of knowledge. All knowledge without exception therefore has only being or ens for its object.

(80) The word ‘TRUE‘ properly speaking expresses a true thing, that is, the conformity of an individual, subsistent being to the intellect. ‘Truth’, however, is ideal ens or the idea of ens.

(81) Sicut in demonstrabilibus oportet fieri reductionem in aliqua principia per se intellectui nota, ita investigando quid est unumquodque; alias utrobique in infinitum iretur, et sic periret omnino scientia, et cognitio rerum. Illud autem quod PRIMO intellectus concipit quasi NOTISSIMUM, et in quo omnes conceptiones resolvit, est ENS. — Unde oportet quod omnes aliae conceptiones intellectus accipiantur ex additione ad ens. Sed enti non potest addi aliquid quasi extranea natura, per modum quo differentia additur generi, vel accidens subiecto: quia QUAELIBET NATURA ESSENTIALITER EST ENS: — sed secundum hoc aliqua dicuntur addere supra ens, inquantum exprimunt ipsius MODUM, qui nomine ipsius entis non exprimitur. — Convenientiam vero entis ad intellectum exprimit hoc nomen VERUM (De Verit., q. 1, art. 1).

(82) In fact the idea of being expresses and represents, that is, makes known, what is present in every real ens. There is a similarity therefore between being as subsisting and being as ideal: the former is possible being, the latter, the same being, but in act. From this comes the well-known distinction made by the whole of antiquity between potency and act. The distinction is certainly mysterious and difficult to grasp, but that does not entitle us to deny it. It is a fact acknowledged throughout history and by all peoples and schools. We have to begin from it as from a primary fact. Although extraordinary and obscure to us, it is a fact, and therefore an undoubtable truth. A false method of philosophy, boastful ignorance and proud modesty may harm itself by refusing to recognise this fact, but it cannot eliminate it.

(83) ‘Of the knower’, that is, of the idea in the knower. This idea is intimately and formally joined to the human spirit, and therefore all that belongs to the idea is attributed to the spirit. Hence, Aristotle says: ‘The soul is in some way all things’ (De Anima, bk. 3, test. 37). The uncertainty of this opinion is evident by his inclusion of ‘in some way’, which indicates a kind of uncertainty in the concept. The opinion, expressed in clear, appropriate words, would be: ‘The idea of being, innate in the intelligent soul and essential to it, is or rather becomes all things in their state of possibility.’

(84) That is, with the idea of the thing. This idea is in the intellect.

(85) In so far as the idea is occasioned or determined in us by that ens, the relationship between a subsistent being and its idea constitutes truth, that is, makes the object true. But the idea itself, as perfect and specific, and considered in its relationship with the entia referred to it, is the truth of these entia.

(86) Things present us with knowledge of themselves according to the degree of their metaphysical truth, that is, of their correspondence to the exemplar-idea (in the Creator) whence they originate. But we would still be unable to know things even if true, were they not true relative to us; we know them, that is, only if an exemplar-idea is in us to make them known, that is, a truth which is the innate idea of being.

(87) Omnis autem cognitio perficitur per assimilationem congnoscentis ad rem cognitam, ita quod assimilatio dicta est causa cognitionis. — Prima ergo comparatio entis ad intellectum est ut ens intellectui correspondeat: quae quidem correspondentia, adaequatio rei et intellectus dicitur: et in hoc formaliter ratio veriperficitur. Hoc est ergo quod addit verum supra ens, scilicet conformitatem, sive adaequationem rei et intellectus; ad quam conformitatem ut dictum est, sequitur cognitio rei. Sic ergo entitas rei praecedit rationem veritatis sed COGNITIO EST QUiDAM VERITATIS EFFECTUS (De Verit., 1, 1).

(88) Bk. 4. — Lucretius’ last reason is subtle and worth analysing. In effect he says: if you deny truth, you deny knowledge. It is clear that you contradict yourself not only by affirming you do not know truth, when the affirmation means presenting a proposition as true, but also by using the words ‘truth’ and ‘falsity’, ‘to know’ and ‘not to know’. If you know the meaning of these words, you already know what truth and falsity are, what to know and not to know are. Can you know all that when, according to yourself, truth, falsity, knowing, or not knowing cannot be known? Truth in fact is not something outside the intellect; it is in the intellect. If you have some knowledge in your intellect, you have some truth. Remove this truth and you remove the knowledge. And if you remove the knowledge, you remove language. You simply become ignorant, like mute animals, incapable of defending or attacking truth. You are no longer a sect of philosophers or even human beings, but brute animals. This is the only possible effect of scepticism coherent with itself. It cannot ask any more questions; it is dumb; its system affects only itself. To declare oneself a sceptic is synonymous with self-degradation and annihilation.

(89) According to etymology, ‘sceptic’ (from [Greek]) expresses one who observes, investigates without any definite conclusion. If we consider that the philosophical disputes are concerned with highly reflective knowledge, and that reflection is subject to disturbance by an infinite number of causes (which must have been the case especially in pagan times) we cannot wonder that scepticism came into being at such a period. Scepticism developed from the exaggeration of a good principle, from a kind of diffidence, a just doubt of oneself, a prudent suspension of judgment, which, according to Socrates, is the form of wisdom itself. Pyrrho’s practical reason, which directs the human being to act according to necessity and the probable advantages of life, disguises the right principle that ‘we must often decide to act upon mere probabilities’. This fact proves our free activity and, because following our will as a norm is a practical assent, indicates the influence of the will in our practical assent to a proposition.

(90) Hence the opinion of St. Thomas that it is impossible for a human being to think that truth does not exist: Nullus potest cogitare veritatem non esse [No one can think that truth is not] (De Verit., q. 10, art. 12). To think and simultaneously to deny truth is a contradiction. The true sceptic cannot exist, and those who claim to be such, either do not know what they are saying, or are lying, as will be clearly seen later.