Supposition and Truth in Ockham's Mental Language

Supposition and Truth in Ockham’s Mental Language ABSTRACT. In this paper, Ockham’s theory of an ideal language of thought is used to illuminate problems of interpretation of his theory of truth. The twentieth century idea of logical form is used for finding out what kinds of atomic sentences there are in Ockham’s mental language. It turns out that not only the theory of modes of supposition, but also the theory of supposition in general is insufficient as a full theory of truth. Rather, the theory of supposition is a theory of reference, which can help in the determination of truth values within the scope of simple predications. Outside this area, there are interesting types of sentences, whose truth does not depend on whether the terms supposit for the same things or not for the same things. 1. Introduction Throughout his writings, William Ockham is defending a programmatic view of an ideal mental language. In this paper, I will sketch some semantical features of this language. My intention is not to give a full picture of Ockham’s thoughts on the language of thought. Rather, my aim is to illuminate problems of relating his conception of truth to the so-called theory of supposition. Modern commentators have mostly interpreted the gist of the theory of supposition as a theory of reference. As such, it is seen to provide a basis for a theory of truth. However, in recent discussion it has been recognized that this interpretation does not fit an important part of the theory. The doctrine that is known as the doctrine of modes of supposition seems to work badly, if at all, when it is used as a straightforward theory of truth.1 Instead of analyzing the theory of modes of supposition, I will here adopt another route towards a solution of these problems. I will work out a more exact picture of Ockham’s views on the relation between the suppositions of the terms and the truth value of the sentence. It seems that a more adequate view of the role of modes of supposition can be achieved from this vantage point. Let us start with a short description of Ockham’s Topoi 16: 15–25, 1997.  1997 Kluwer Academic Publishers. Printed in the Netherlands. Mikko Yrjönsuuri mental language as a language.2 After this description it is easier to go deeper to the semantical particulars. 2. Mental language as an ideal language It is quite natural that Ockham thought that the possibilities of expression are in a sense complete in the mental language. Everything that can be thought of can be expressed in it, since it is not a mere medium of expressing thoughts. Mental language is the universal medium of thinking since it is the language that thought itself takes place in. Consequently, all the different meanings that can be expressed in spoken languages, like Ockham’s Latin, can be expressed also in mental language. Ockham recognizes that the external characteristics of Latin words naturally need not be reflected in their mental equivalents. However, all such features that have an effect on the truth of a sentence must also be found in the mental equivalent of the sentence. Mental language has nothing to correspond to mere non-significative ornaments of speech, like gender, but it can express all significative differences.3 In his classic work Mental Acts, Peter Geach criticized Ockham for merely copying the accidental characteristics of Latin to mental discourse. John Trentman later corrected Geach’s mistake in an interesting little article.4 Ockham’s project in his study of the mental language was the project of a logician. He wanted to describe an ideal language, perhaps the ideal language of all intellects. It is true that Ockham’s starting point is exclusively Latin. He accounts for the characteristics of mental language in relation to those of Latin. However, given the general fourteenth century logical practises, Ockham’s procedure is more accurately described as distinguishing mental language from Latin than assimilating the two languages. After all, Latin was the universal language of scientific discussion for the logicians of the period. 16 MIKKO YRJÖNSUURI It seems that Ockham leans on a relatively good systematic basis for inferring characteristics of mental language from those of Latin. He accepts the standard Aristotelian idea that mental language is related to spoken language in the same way as spoken language is related to written language. Just as written language transfers and translates the spoken discourse of sounds into ink on paper, spoken language transfers and translates the immaterial discourse of mental events into an articulate string of sounds. A sentence of a spoken language aims at expressing that which is expressed by a mental sentence. Consequently, the structure of all spoken languages must in some way reflect the structure of the mental language. A systematic survey of the possibilities of expression contained in a spoken language can also reveal what can be expressed in the mental language. It is worth recognition that Ockham’s mental language was not just an idealization of Latin. He describes it from another direction as a presupposition of all thinking. Ockham thought that all thinking must take place in an essentially similar form because mental acts reflect directly the natural structure of the world. Concepts – the vocabulary of the mental language – are not for Ockham “mere figments” of the mind. Rather, they are based on what the world really is like. This view is stated in an especially clear way in connection with the following curious example taken from Duns Scotus. Let us compare Plato, Socrates and a line. According to the nominalist claim, Plato and Socrates are individuals which have nothing in common. Thus, Ockham’s opponent argues, the intellect has no basis for gathering them under the same concept as distinct from the line. As an answer Ockham simply claims that Plato is more similar to Socrates than to the line. This similarity is based on the fact that they are men.5 For Ockham, it is a crude fact that Plato and Socrates fall under the concept ‘man’ and the line does not. This fact does not depend on the mind forming the concept ‘man’. On the contrary, any intellect would form the concept in exactly the same way. Since this is not only true for the concept ‘man’, but equally for all concepts, the resulting mental language containing these concepts as its vocabulary would be the same for all intellects. Thus, Ockham has clear systematic grounds for his assumption that this language is universal. 3. Logical form and supposition of the terms One of the grand ideas of twentieth century analytic philosophy has been to search for the correct analysis of troublesome sentences. The paradigmatic example of a successful analysis has been Russell’s discussion of the sentence ‘the present king of France is bald’ in his famous paper “On denoting”. It is well known that the logical form of this sentence is actually not just predication. Rather, the sentence claims that a certain kind of object exists. It has often been pointed out by modern commentators that Ockham also endorsed something closely analogous to such a search for logical form. Indeed, Bertrand Russell is often mentioned in footnotes of studies of Ockham’s semantical theories. It seems clear that Ockham’s theory of mental language is an important part of this program. Since mental language is an ideal language, mental sentences ought to have the correct logical form. From this viewpoint, Ockhamist translation of Latin sentences into mental expressions seems to correspond to what a representative of twentieth century analytic philosophy aims at by translation of English expressions into a formal calculus. Given the Aristotelian framework of Ockham’s logic, it is natural that predication is the leading idea in his description of the logical form of statements. His sentential analysis is paradigmatically concerned with universal or particular and affirmative or negative predications of the form ‘S is P’. For predications with simple and unproblematic terms, the traditional square of opposition gives the four standard cases of correct logical form. In book II of his textbook of logic, Summa logicae, Ockham discusses logical properties of propositions (indicative sentences). The main problem addressed in this discussion is that of giving truth conditions for different kinds of propositions. A twentieth century reader trained in the tradition of analytic philosophy can scarcely avoid the impression that Ockham’s aims in these chapters are guided by the idea that the logical form of a sentence should be used in the determination of its truth value. Ockham seems to first give the truth conditions for the four kinds of irreducible categorical propositions found in the traditional square of opposition. Then he goes on to show how other propositions can be reduced to these forms. The medieval theory of supposition seems to form the basis of Ockham’s procedure. For him, the truth of an affirmative singular predication ‘S SUPPOSITION AND TRUTH IN OCKHAM’S MENTAL LANGUAGE is P’ requires that ‘S’ and ‘P’ in this sentence supposit for (stand for, refer to) the same object. Thus, ‘this is an angel’ is true if and only if ‘angel’ supposits in this sentence for the object demonstrated by the demonstrative pronoun ‘this’.6 The whole variety of simple categoricals is treated by Ockham with reference to the so called doctrine of modes of supposition. For instance, the truth of ‘some animal is a man’ requires only that there is some singular case where ‘this animal is a man’ is true. That is, it requires only that the two terms supposit for at least one same object.7 Similarly, ‘every animal is a man’ is false because ‘man’ does not supposit for all those things that ‘animal’ supposits for in this sentence. The subject term in this sentence has the so called distributive mode of supposition, and consequently the predicate term should supposit for all those things that the subject term supposits for.8 If we were to read Ockham’s discussion in a simple and straightforward manner, his program would look like the following: An affirmative singular predication is true if the terms supposit for the same object. Similarly, a negative singular predication is true if the terms do not supposit for the same object. On this reading the theory of supposition would thus provide us the basic truth conditions of singular predications. The theory of modes of supposition would then guide us in reducing all the four simple categoricals found in the square of opposition into singular predications. All other kinds of sentences could be reduced to the simple categoricals through more complicated systems. Thus, truth would always be determined by the principle that in affirmative predications terms supposit for the same and in negative predications they do not supposit for the same. In fact, modern scholars of supposition theory have noticed that Ockham’s doctrine of the modes of supposition does not fit this scheme. It does not play the role one would expect it to play in the model sketched above.9 As I see it, the model is misleading already in a more fundamental way. In my reading of the texts, it seems that Ockham did not think that all propositions would be reducible to the four simple categoricals. If we look at the full richness of mental language as it is described by Ockham, it turns out that it needs a richer theory of truth. It is impossible to determine the truth values of all mental sentences by the principle that the subject and the predicate ought to supposit for the same in affirmative and not for the same in negative propositions. In fact, this principle gives us only a 17 starting point. Simple categoricals form the core of Ockham’s logical theory, but for a general theory of truth other kinds of sentences need attention, too. In the following sections I will shed some light on the variety of different kinds of irreducible (atomic) sentences recognized by Ockham. 4. Grammatical structures of mental language According to a general division given in Summa logicae I, ch. 4, there are categorematic and syncategorematic terms both in mental and in spoken language. Categorematic terms are those which have a definite signification, while syncategorematic terms do not signify anything by themselves. Ockham’s example is clear and straightforward. According to him, the word ‘man’ is a categorematic term signifying all men. On the other hand, ‘every’ is a syncategorematic word, which does not signify any definite thing. Ockham describes its function by the claim that “when it is combined with the term ‘man’, it makes that term stand or supposit confusedly and distributively for all men.” 10 That is, Ockham gives as the primary example of the function of syncategorematic expressions a case of an effect on the mode of supposition of the categorematic parts of the sentence. When we look at Ockham’s general descriptions of categorematic and syncategorematic terms more closely, we notice that categorematic terms are much easier to describe than syncategorematic terms. Ockham says straightforwardly: “Categorematic terms have a definite and determinate signification”.11 If we compare this description to Ockham’s definition of signification – “a sign is said to signify something when it supposits for or is capable of suppositing for that thing”12 – it becomes clear that categorematic terms determine which things are being talked about. The parts of sentences that supposit for external things are categorematic. The general description of syncategorematic terms is much more complicated and much less illuminating: “a syncategorematic term does not, properly speaking, signify anything; however, when it is combined with a categorematic expression it makes that categorematic expression signify something or supposit for something in a determinate manner, or it performs some other function with regard to the relevant categorematic term.”13 It seems that Ockham’s point is that the general function of a syncategorematic expression is to modify 18 MIKKO YRJÖNSUURI the sentential role of the categorematic term that it is attached to. As the primary case, he picks out the effect on the mode of supposition. However, he does not exclude any kind of effect. Rather, the description looks more like a claim that there are also other kinds of effects. If categorematic terms determine which things are being talked about, syncategorematic terms determine how they are being talked about and what is actually said about them. From Ockham’s discussion, the reader gets the impression that the core of linguistic discourse (whether mental or spoken) consists of terms having supposition and markers of the modes of supposition that these terms have. We can see quite quickly that the doctrine of modes of supposition shows that simple categoricals belong to this core. However, there is something more. Ockham recognizes that there are syncategorematic expressions for quite a variety of functions also in mental language. We can see his reasons for admitting them easily, if we evaluate Ockham’s discussion of mental language with respect to the task of describing an ideal language. Ockham does not approach his aim from the same angle as twentienth-century constructors of a formal calculus. He is not beginning from a small set of logical constants to serve as syncategoremata and then trying to look at how rich a language could be constructed from these constants together with categorematic terms. Rather, he is beginning from spoken Latin, and trying to explain all Latin expressions in terms of mental language. Ockham’s most explicit discussion of what is contained in mental language is in Summa logicae, I, ch. 3. The method of this discussion is to take up linguistic distinctions of spoken Latin in order to see whether they are necessary. In several interesting cases Ockham admits that there must be something in mental language to correspond to a linguistic distinction of spoken Latin. For instance, there must be something to correspond to cases of nouns. As Ockham says, the predicates of ‘man is man’ and ‘man is not man’s’ are different, and this difference is of relevance to determining the truth values of these two statements. Indeed, the affirmative sentence is tautologically true while the negative one ought not be false. Thus, the predicates must be different and there must be differences of case in mentalese.14 Ockham’s point seems to be that in order to produce differences like this a syncategorematic expression is added to one of the predicates. Thus, there must be a syncategorematic expression corresponding to the genitive ending. However, it seems clear that the function of this syncategorematic expression cannot be accounted for as an effect on the mode of supposition of the predicate of this sentence. When Ockham discusses truth conditions of categorical sentences, he includes a little chapter on propositions with terms in oblique cases (all of the cases other than the nominative). (Summa logicae II, c. 8.) This chapter has been paid little attention, probably because Ockham himself says that he just “quickly mentions some useful rules” on the issue. However, it seems that the treatment of propositions with terms in oblique cases has some systematic importance, since Ockham explicitly says that evaluation of suppositions is of little use in this case. If an affirmative proposition has a term in an oblique case, its truth does not require that the terms supposit for the same. For example, the truth of the affirmative sentence ‘some donkey is Socrates’s’ requires (but it is not sufficient) that subject and predicate supposit for different things. The predicate ought to supposit for Socrates and the subject for his donkey.15 5. Connotative terms Ockham refers to oblique cases also in a context whose systematic importance has been recognized by modern scholars. Let us now turn to this context for a wider discussion. Ockham distinguishes a certain group of terms, which signify one thing primarily and another thing secondarily. He calls these terms ‘connotative’, and contrasts them to ‘absolute terms’, which signify in an equally primary way all the things that they signify. The absolute term ‘animal’ does signify both men and donkeys, but in an equally primary way, and consequently there is no interesting need for oblique cases of nouns when its signification is spelled out. On the other hand, when the signification of a connotative term is spelled out, oblique cases are required.16 Ockham’s favourite example of a connotative term is ‘white’. According to Ockham, this term primarily signifies the subject of the color, and secondarily the color itself. We can also say that the term (normally) supposits for the subject of the color, not for the color itself. With a demonstrative pronoun (‘this is white’) the term picks out the white thing, not the whiteness itself. Nevertheless, the term can be appropriately used for the SUPPOSITION AND TRUTH IN OCKHAM’S MENTAL LANGUAGE thing only if the quality of whiteness inheres in it. Thus, the term ‘white’ signifies also whiteness, but in a different manner. According to Ockham, the signification of a connotative term can be given by a nominal definition which usually contains terms in oblique cases. In Ockham’s Latin ‘albus’ (white) can be defined ‘aliquid habens albedinem’ (something having whiteness), where ‘aliquid’ is in the nominative case and ‘albedinem’ is in the accusative case.17 Ockham’s remark may seem arbitrary or at best language-dependent. In English the same example lacks the distinction made by Ockham. However, there seems to be a deeper point behind his suggestion. The manner in which ‘white’ refers to whiteness cannot be expressed by a straightforward predication containing only the ordinary copula and terms in the nominative case. Consequently, if Ockham for logical reasons prefers to use ‘whiteness’ rather than ‘white’ in his mental sentences, he is forced to accept alternative structures of predication in order to make claims about whiteness. However, the syncategorematic structure of the sentence ‘this has whiteness’ (hoc habet albedinem) is more complicated than the syncategorematic structure of ‘this is an angel’ (hoc est angelus), which I mentioned above as an example of singular predication (see footnote 6). In Latin the difference is more explicit than in English, but in both languages we can see that the truth of the former does not depend simply on the terms having supposition for the same or not for the same thing. It is evident that connotative words having in their signification the double structure described by Ockham are rather common in ordinary languages. Accordingly, Ockham provides a large number of examples of connotative terms. These examples belong to a variety of different groups.18 First, there are connotative terms functioning in a similar way as ‘white’. Ockham’s examples are ‘just’, ‘besouled’, and ‘human’. These terms signify primarily the subject of the property, which is signified secondarily. Second, all terms expressing relations are connotative. Ockham’s example is ‘similar’, but elsewhere he uses simpler examples like ‘father’ or ‘son’. Ockham’s idea is that terms cannot refer to relations (which in his view do not really exist). Instead, the reference is to one of the relata. Third, since Ockham thought that quantities do not exist separately from their subjects, he claims that 19 quantitative terms are connotative. The examples are ‘solid’, ‘continuous quantity’, ‘figure’, ‘curvature’, ‘straighness’, ‘length’ and ‘height’. After these unified groups, Ockham lists a group of important technical terms of philosophy: ‘true’, ‘good’, ‘one’, ‘potency’, ‘act’, ‘intellect’, ‘intelligible’, ‘will’, and ‘desirable’. The point seems to be just to recognize that there are lots of other kinds of connotative terms, too. The common property of all connotative terms is that they have a certain duplicity in their manner of signifying. Ockham seems to think that this is based on the terms themselves being complex. Absolute terms, which have only one mode of signifying, are essentially simple. Thus, several modern commentators have thought that Ockham would not allow any room for irreducible connotative terms in his mental language.19 It seems that an ideal language ought to be built only from essentially simple elements. It may be worth recognition that Ockham gives the distinction between absolute and connotative terms among those divisions that apply equally to both mental and spoken languages.20 Thus, he seems to accept that in some sense there are mental connotative terms. However, his idea might be that mental connotative terms are in fact complex constructs consisting of absolute terms and syncategorematic expressions. These constructs would be called connotative terms just for the sake of simplicity. The crucial question is whether connotative terms are reducible or not. 6. Reduction of connotative terms Ockham seems to offer a method of reducing connotative terms into less problematic expressions, when he claims that all connotative terms have a nominal definition but no real definition. It is clear that a connotative term cannot have a real definition, since there is no one thing to correspond to a connotative term as its significate. Thus, there is really nothing to define. It seems equally clear that connotative terms may have nominal definitions. Their meaning can be explained by phrases constructed from less problematic terms. In the chapter dedicated to definitions, Ockham claims that any part of a sentence can be given a nominal definition. As an example he gives the following nominal definition: “ ‘where’ is an interrogative adverb of place”.21 20 MIKKO YRJÖNSUURI As we saw above, the nominal definition of ‘white’ could be ‘something having whiteness’. Some connotative terms are more complex. According to Ockham, the term ‘good’ is to be defined as ‘something which, according to right reason, can be willed and loved’.22 In some modern interpretations it has been suggested that connotative terms should be simply replaced by their nominal definitions. However, this strategy seems to be contradicted by some of Ockham’s examples of nominal definition (such as ‘where’ above). It does not seem that Ockham would have intended nominal definitions generally as replacements for the defined terms. Rather, nominal definitions explain the meaning and function of the term at issue. As such, nominal definitions cannot serve as a straightforward manner of reduction. As I see it, this does not prove that there are irreducible mental connotative terms. Such a conclusion follows if we consider only reductions proceeding termby-term. However, in my view we should also allow the possibility of a reduction sentence-by-sentence. Ockham considers this method of reduction in the context of the truth conditions of certain kinds of propositions. Summa logicae II, ch. 11 has the title “On Propositions which, though Categorical in Form, are Equivalent to Hypotheticals”. In the subsequent chapters (up to ch. 20) Ockham considers propositions whose truth is to be found out by analysis into a molecular form. His point seems to be that the superficial structure of these propositions does not accurately reflect their logical form. In Summa logicae II, ch. 11 Ockham’s list of the types of such (so called exponible) propositions is not very careful, and thus it may be incomplete. Still, it is interesting. He mentions exclusive, exceptive and reduplicative propositions as a first group. These kinds of sentences share the property that they may consist solely of absolute terms together with certain special syncategorematic words (only, except, insofar as). In Ockham’s own words, the second group consists of “propositions in which connotative or relative terms occur”.23 Ockham also gives a reason why all propositions containing connotative terms are exponible. It is due to the fact that a connotative term cannot supposit for all those things that it signifies. Ockham points out that ‘whiteness is white’ is false because the predicate cannot supposit for the things that the subject supposits for. ‘White’ does signify whiteness, but only secondarily, and thus it cannot supposit for the property.24 In order to consider the sentential import of the secondary significations of connotative terms, the proposition must be expounded. The guidelines for how to make the exposition can according to Ockham be seen from the nominal definition of the term at issue. Indeed, Ockham says that the exponents “express what is meant by such a proposition”, which is a formula he uses also for nominal definitions.25 Ockham does not give rules of how to construct the exposition, but examples are illuminating. For example, the nominal definition of ‘white’ is ‘something having whiteness’ (aliquid habens albedinem). Thus, the sentence ‘a white thing is running’ (album currit) is to be expounded into ‘something is running’ (aliquid currit) and ‘whiteness is in that thing’ (illi inest albedo). The original proposition is equivalent to the conjunction of these two exponents.26 Using these guidelines, we could formulate the Ockhamist program of reduction of connotative terms as a process of exposition. The idea would be to expound all expressions with connotative terms. If any of the exponents still has connotative terms, it can be further expounded. Ultimately, the result would be a molecular expression containing only absolute and syncategorematic terms. Thus, all terms could supposite in the sentence for all those things that they signify. The resulting irreducible form would contain no secondary significations. It seems quite appropriate to claim that the result of such reduction reflects the real logical form of the statement.27 In many cases, the full exposition of a sentence may not be easily visible. Also, the resulting molecular sentence may look very complicated. Ockham considers these problems in an interestingly explicit way in his discussion of time in Summula philosophiae naturalis, book IV. In chapter 10 he attacks the position of those who think that “all nouns supposit determinately for some thing in the way in which ‘whiteness’ and ‘man’ supposit.”28 Ockham’s idea is that ‘time’ and ‘instant’ are examples of connotative terms, which have only nominal definitions. Consequently, they are to be analyzed away in the sentential context where they occur. In Ockham’s own words: “it should be understood that this noun ‘time’ is used instead of long phrases, and similarly short propositions are sometimes used for long ones so that they are put together from other terms than those placed in the short propositions.”29 Ockham’s examples of the analysis proceed in two basically different manners. In some cases the word SUPPOSITION AND TRUTH IN OCKHAM’S MENTAL LANGUAGE ‘time’ ought to be replaced by some longer phrase. Ockham’s example for a replacement is “something changing very fast and uniformly so that by considering it an intellect can make certain how much or how long something changes, lasts or is in rest”.30 This is a case where reduction of a connotative term takes place termby-term. Ockham gives also a clear example of a sentence-bysentence analysis: “instead of this: ‘time is continuous’ one should put this whole phrase: ‘something changes uniformly and very fast without stopping’.”31 7. Exposition and supposition At this stage, let us return to the problem of relating truth and supposition. As we saw in the preceding section, there need not be any irreducible mental connotative terms, since they can be analyzed by exposition of the whole sentence at issue. Exposition of the sentence produces an expression consisting of absolute terms together with syncategorematic expressions. Now, in order to determine the truth value, we need more advice. Should we tackle the problem in the twentieth century truth-functional way? That is, should we determine the truth value of this molecular sentence by determining the truth values of its atomic parts? And further, should we lean on the theory of modes of supposition for deciding the truth values of the atomic parts? It seems that Ockham accepts the truth-functional procedure quite a bit. In a paradigmatic case exposition produces a conjunction equivalent with the original sentence. Then each of the conjuncts can be evaluated separately. However, a closer look shows that Ockham did not use the theory of modes of supposition to determine the truth values of the atomic sentences. In fact, he analyzes the modes of supposition before exposition, not after it. Let us look at an example: the mode of supposition of ‘white’ in the exponible sentence ‘Socrates begins to be white’. Ockham discusses this issue twice in his Summa logicae, first in the section discussing the modes of supposition, and second in the section discussing truth conditions of exponible propositions. In Summa logicae I, ch. 75, Ockham first points out that whatever the mode of supposition is, it does not follow the so-called rules of descent to particulars for the standard modes (determinate, merely confused, 21 confused and distributive). Ockham’s conclusion is the following: “It has a different form of supposition for which we have no name.” After this he goes into a discussion of the characteristics of this mode.32 In this context Ockham closes the discussion with an interesting remark. He points out that in the expounded form (‘Socrates was previously not white and now for the first time is white’) the predicate term (‘white’) occurs in two different suppositions, since it is predicated both negatively (in the past tense) and affirmatively (in the present tense) of the subject. As a result, the supposition of ‘white’ in ‘Socrates begins to be white’ is a combination of two different modes of supposition (determinate together with confused and distributive), since the proposition is in fact a combination of two different propositions.33 In Summa logicae II, ch. 19, Ockham’s explanation is slightly different. There he takes the position that the mode of supposition of ‘white’ in ‘Socrates begins to be white’ is merely confused of a special type. In this context, Ockham points out that the rules of descent for merely confused supposition turn out to work, if they are applied in an alternative way. One ought not to pick out the particular things simply with a demonstrative pronoun, but with a demonstrative pronoun combined with the term ‘white’. That is, from ‘Socrates begins to be white’ it follows that (we can descend to) ‘Socrates begins to be this white thing or he begins to be that white thing or etc.’ On the other hand, the disjunction ‘Socrates begins to be this or he begins to be that or etc.’ suggested by standard rules of descent does not follow (it is not possible to descend to it). The difference between these two kinds of descent is in effect that the connotative (secondary) signification of ‘white’ is retained in the former but not in the latter. Since the descent is constructed in a non-standard manner, the mode of supposition must also be non-standard.34 In this case Ockham is determining the mode of supposition for the predicate of the exponible sentence and not for the predicates of the expounded form. Consequently, he is not requiring that the sentence should be stated in the correct logical form before the modes of supposition of the terms is to be decided. If modes of supposition were the method of determining truth, this order of proceeding would be wrong. It seems clear that Ockham is not using the theory of modes of supposition to describe the truth conditions of exponible sentences. Not even as applied to the expounded form. 22 MIKKO YRJÖNSUURI 8. Simple facts Let us look more closely at the kinds of atomic sentences produced as the results of expositional analysis of connotative expressions. This way we can see quite easily the reason why Ockham is not using the theory of modes of supposition to determine their truth values. For him, the variety of different kinds of atomic sentences is simply too wide for such a simple technique. Let us return to the simplest possible example of an exponible sentence, the claim that Socrates is white. Ockham’s exposition of this sentence is ‘Socrates exists and whiteness is in Socrates’ (Sortes est et Sorti inest albedo).35 The first conjunct seems relatively unproblematic. The second deserves more attention. It seems that Ockham did not think that the latter conjunct of this expounded expression would contain any more connotative or other terms requiring exposition. It should be viewed as an atomic proposition expressing the fact that an absolute property of whiteness inheres in Socrates. The sentence ‘whiteness is in Socrates’ (Sorti inest albedo) contains two absolute terms, ‘Socrates’ and ‘whiteness’. However, the syncategorematic link between these two terms cannot be spelled out as the two terms having supposition for the same. Socrates is not whiteness, he is white. In this example, the theory of modes of supposition cannot help us, because even the general theory of supposition cannot help. Instead, it seems that in order to find rules for deciding the truth of this simple sentence, we should go to Summa logicae II, ch. 8, where Ockham discusses propositions with terms in oblique cases. However, as we noticed before, his discussion in this chapter is very scanty, and thus it seems necessary to turn elsewhere. An interesting text to compare with this analysis is Ockham’s discussion of intuitive knowledge in the first question of the prologue of his Ordinatio. There he distinguishes two kinds of knowledge that can be achieved by simple intuitive perception. First, knowledge of existence. When one perceives something intuitively, one achieves knowledge of the existence of this thing. This kind of knowledge seems to be needed in order to know the truth of the first conjunct (Socrates exists) of the expounded form of ‘Socrates is white’.36 Second, intuitive cognition of external things gives also knowledge of contingent facts about these things. Ockham says: “Similarly, intuitive knowledge is such that when one cognizes things of which one inheres in another or one is at a local distance from another or is in some other way related to another, then one knows immediately in virtue of this incomplex knowledge of these things whether the thing inheres or not, whether it is at a distance or not, and so also for other contingent truths.”37 In this passage, Ockham takes the position that relations of inherence, local relations and also other kinds of relations can be known through simple mental acts of intuitive cognition. His example is knowledge of the fact that Socrates is white. For this knowledge, one perceives Socrates together with his whiteness in such a way that the relation of inherence becomes known. It is noteworthy that Ockham does not say that one would perceive Socrates as a white thing. According to him, one perceives two existing things, Socrates and his whiteness. Consequently, the atomic sentence expressing the content of this perception cannot consist of two terms suppositing for the same thing. Its syncategorematic structure is more complicated. It must contain syncategorematic terms to express the relation of inherence. It seems clear now that Ockham did not intend to reduce all truth conditions to the principle that in affirmative predications the terms supposit for the same and in negative predications they do not supposit for the same. Instead, he recognizes that there are important classes of atomic sentences whose truth depends on more complicated structures. 9. Conclusion If at least the main tenet of my interpretation of Ockham’s theory of truth is correct, the standard reading of Ockham’s principle ‘truth requires that the terms supposit for the same’ is mistaken. Thus, it seems appropriate to conclude with a comment on how we should instead read this principle. Usually, this principle is taken to be Ockham’s general formulation of what truth is. In my reading, it explains only the truth of a certain group of propositions. However, it must be noticed that this group is by far the most important subclass of propositions for a fourteenth-century logician. Aristotelian syllogistics is based on propositions belonging to this group. Ockham explicitly recognizes in Summa logicae II, ch. 8 that the truth values of propositions with terms in oblique cases do not depend on the terms suppositing SUPPOSITION AND TRUTH IN OCKHAM’S MENTAL LANGUAGE for the same or not for the same thing. That such a small amount of text is dedicated to this group of propositions suggests that Ockham did not give this group much systematic weight. My interpretation requires that this class of propositions is valued higher than its share of the quantity of text in book II of the Summa logicae. Indeed, if my interpretation is corrrect, this group of propositions has a key position in Ockham’s epistemology. The basic statement of the principle that in true affirmative predications the terms supposit for the same things is to be found in Summa logicae II, c. 2. In this chapter, Ockham does not give the principle as a general theory of truth. It is applied just to the truth of “singular non-modal present-tense propositions, whose subjects and predicates are both in the nominative case and which are not equivalent to hypothetical propositions.”38 In Summa logicae II, c. 2 Ockham uses the principle to oppose those theories which suppose some kind of real union of the predicate with the subject. Thus, Ockham introduces the theory of supposition in order to support his nominalism. His idea is that the sentential role of absolute terms can be completely described in terms of their suppositions, and the theory of truth does not require metaphysical realism. On the other hand, in order to support his nominalism Ockham does not need to limit the available syncategorematic structures. There is no metaphysical motivation to reduce all sentences to truth-functional combinations of basic singular predications consisting of absolute terms in the nominative case. In fact, a wider selection of basic syncategorematic terms carries no metaphysical cost but gives higher epistemological benefits. Notes 1 Cf., e.g., Priest and Read 1980; Read 1991; Schaeffer 1987; Scott 1966 and especially Spade 1988. For general discussions of theory of supposition as a theory of truth see also Alféri 1989, esp. pp. 299–401 and Panaccio 1991, esp. pp. 43–56 and pp. 190–205. 2 For wider discussion see, e.g., Karger 1994; King 1985; Normore 1990; Panaccio 1992. 3 Cf. Ockham 1974, pp. 11–14. (Summa Logicae I, ch. 3.) 4 Trentman 1970. 5 “Ad illud quod innuitur in illo argumento, quod si omnis diversitas esset numeralis non plus posset intellectus abstrahere a Sorte et Platone aliquid commune quam a Sorte et linea et quod quodlibet universale esset purum figmentum intellectus, dico ad primum quod ex hoc ipso quod Sortes et Plato se ipsis differunt solo numero, et 23 Sortes secundum substantiam est simillimus Platoni, omni alio circumscripto, potest intellectus abstrahere aliquid commune Sorti et Platoni quod non erit commune Sorti et albedini; nec est alia causa quaerenda nisi quia Sortes est Sortes et Plato est Plato et uterque est homo.” Ockham 1970, pp. 211. (Ordinatio II, d. 2, q. 6.) 6 “Sufficit et requiritur quod subiectum et praedicatum supponant pro eodem. Et ideo si in ista ‘hic est angelus’ subiectum et praedicatum supponant pro eodem, propositio erit vera.” Ockham 1974, p. 250. (Summa logicae II, c. 2.) 7 “Et ad veritatem talium sufficit quod subiectum et praedicatum supponant pro aliquo eodem . . . Sicut ad veritatem istius ‘aliquod animal est homo’ sufficit veritas istius ‘hoc animal est homo’ vel ‘illud animal est homo’.” Ockham 1974, p. 255. (Summa logicae II, c. 3.) 8 “. . . requiritur quod praedicatum supponat pro omnibus illis pro quibus supponit subjectum, ita quod de illis verificetur . . . Et hoc est quod communiter dicitur quod ad veritatem talis propositionis universalis sufficit quod quaelibet singularis sit vera.” Ockham 1974, p. 260. (Summa logicae II, c. 4.) 9 See esp. Spade 1988. 10 “. . . hoc syncategorema ‘omnis’ non habet aliquod certum significatum, sed additum ‘homini’ facit ipsum stare seu supponere actualiter sive confuse et distributive pro omnibus hominibus; additum ‘lapidi’ facit ipsam stare pro omnibus lapidinis; et additum ‘albedini’ facit ipsam stare pro omnibus albedinibus. Et sicut est de isto syncategoremate ‘omnis’, ita proportionaliter de aliis est tenendum, quamvis distinctis syncategorematibus distincta officia conveniant.” Ockham 1974, p. 15; translation by Loux 1974, p. 55. (Summa logicae I, c. 4.) 11 “Termini categorematici finitam et certam habent significationem.” Ockham 1974, p. 15; translation by Loux 1974, p. 55. (Summa logicae I, c. 4.) 12 “Uno modo dicitur signum aliquid significare quando supponit vel natum est supponere pro illo.” Ockham 1974, p. 95; translation Loux 1974, p. 113 (Summa logicae I, c. 33). For a clear discussion of the relation between Ockham’s concepts of signification and supposition see Biard 1989, pp. 74–96. 13 “. . . syncategorema proprie loquendo nihil significat, sed magis additum alteri facit ipsum aliquid significare sive facit ipsum pro aliquo vel aliquibus modo determinato supponere vel aliud officium circa categorema exercet.” Ockham 1974, p. 13; translation by Loux 1974, p. 55. (Summa logicae I, c. 4.) 14 “Similiter sicut istae propositiones vocales ‘homo est homo’ et ‘homo non est hominis’ habent distincta praedicata variata per casus, sic proportionaliter dicendum est de propositionibus in mente correspondentibus.” Ockham 1974, p. 12; translation by Loux 1974, p. 53. (Summa logicae I, c. 3.) 15 “Unde quando casus obliquus regitur ex vi possessionis, ad veritatem talis propositionis requiritur quod subiectum et praedicatum supponant pro distinctis, quamvis hoc non semper sufficiat. Ideo haec est falsa ‘Sortes est Sortis’, haec tamen poterit esse vera ‘aliquis asinus est Sortis’.” Ockham 1974, p. 272. (Summa logicae II, c. 8.) 16 Ockham’s basic discussion is in Ockham 1974, pp. 35–38 (Summa logicae I, c. 10). Cf. also Ockham 1980, pp. 582–584 (Quodlibet V, q. 25). 17 “Nomen autem connotativum est illud quod significat aliquid primario et aliquid secundario. Et tale nomen proprie habet definitionem exprimentem quid nominis, et frequenter oportet ponere unum 24 MIKKO YRJÖNSUURI illius definitionis in recto et alio in obliquo. Sicut est de hoc nomine ‘album’, nam ‘album’ habet definitionem exprimentem quid nominis, in qua una dictio ponitur in recto et alio in obliquo.” Ockham 1974, p. 36 (Summa logicae I, c. 10). 18 Ockham 1974, pp. 37–38, translations by Loux 1974, pp. 70–71. (Summa logicae I, c. 10.) 19 For discussion of the problem see, e.g., Goddu 1993; Normore 1990; Panaccio 1990 and 1992; Spade 1975. 20 Straight after the discussion of absolute and connotative terms in Summa logicae I, c. 10, chapter 11 begins: “Positis divisionibus quae possunt competere tam terminis naturaliter significantibus quam etiam terminis ad placitum institutis, dicendum est de quibusdam divisionibus competentibus terminis ad placitum institutis.” Ockham 1974, p. 38. 21 “Ubi: est adverbium interrogativum loci.” Ockham 1974, p. 89; translation by Loux 1974, p. 108. (Summa logicae I, c. 26.) 22 “Bonum, etiam, quod est convertibile cum ‘ente’, significat idem quod haec oratio ‘aliquid secundum rectam rationem volibile vel diligibile’.” Ockham 1974, p. 38; translation by Loux 1974, p. 71. (Summa logicae I, c. 10.) 23 “Huiusmodi etiam sunt omnes propositiones in quibus ponuntur termini connotativi et relativi.” Ockham 1974, p. 279; translation by Freddoso 1980, p. 115. (Summa logicae II, c. 11.) 24 Ockham 1974, p. 280; translation by Freddoso 1980, p. 116. (Summa logicae II, c. 11.) 25 “Quaelibet propositio quae habet talem terminum est habens exponentes exprimentes quid importatur per talem propositionem.” Ockham 1974, p. 281; translation by Freddoso 1980, p. 116. (Summa logicae II, c. 11.) 26 “Ad veritatem istius ‘album currit’ requiruntur istae duae ‘aliquid currit’ et ‘illi inest albedo’.” Ockham 1974, p. 281; translation by Freddoso 1980, p. 117. (Summa logicae II, c. 11.) 27 For a wider discussion of how to use expositional analysis to find the hidden logical form see Yrjönsuuri 1993. 28 “Quod quidem omittentes et volentes quod omne nomen determinate supponat pro aliqua re ad modum quo ‘albedo’ et ‘homo’ supponunt, concedunt multas propositiones negatas ad antiquis . . .” Ockham 1984, p. 366. (Summula philosophiae naturalis IV, c. 10.) 29 “Et sic de consimilibus est intelligendum quod utimur hoc nomine tempus pro longa oratione et similiter quandoque utimur propositione brevi pro longa, composita ex aliis terminis quam sint illi qui ponuntur in propositione brevi. Et ideo tales propositiones breves exponendae sunt per alias longas, et per illas longas quae magis propriae sunt et clariores et planiores iudicandum est de aliis.” Ockham 1984, pp. 365–366. (Summula philosophiae naturalis IV, c. 10.) 30 “Et ideo qui dubitant de aliqua propositione in qua ponitur hoc nomen tempus, ponant loco illius hanc totam orationem ‘aliquid movetur velocissime et uniformiter quod considerans intellectus potest certificari quantum vel quamdiu aliquid movetur, durat vel quiescit’, vel aliquam consimilem.” Ockham 1984, p. 365. (Summula philosophiae naturalis IV, c. 10.) 31 “Sicut loco istius ‘tempus est continuum’ debent poni tota ista oratio ‘aliquid sine quiete movetur uniformiter et velocissime’.” Ockham 1984, p. 365. (Summula philosophiae naturalis IV, c. 10.) 32 “Potest dici quod terminus praedicatus in talibus propositionibus . . . non habet suppositionem nec determinatam nec confusam tantum nec confusam et distributivam, sed unam aliam pro qua tamen nomen non habemus.” Ockham 1974, p. 231; translation by Loux 1974, p. 216. (Summa logicae I, c. 75.) 33 “Ratio autem quare terminus talis non habet aliquam praedictarum suppositionum est ista: quia semper illa propositio aequivalet uni copulativae ex duabus vel pluribus propositionibus, quarum aliqua est negativa et alia affirmativa de eodem subiecto, in quibus idem terminus habet diversas suppositionibus; et ideo nullam istarum habet in illa una propositione cuius exponentes sunt istae partes.” Ockham 1974, p. 232; translation by Loux 1974, p. 216. 34 “Aliquando autem contingit descendere non praecise per pronomina demonstrativa sola, sed per pronomina demonstrativa sumpta simul cum illo termino communi sub quo debet esse descensus.” Ockham 1974, p. 313; translation by Freddoso 1980, pp. 149–150. (Summa logicae II, c. 19.) 35 “Sicut ad veritatem istius ‘Sortes est albus’ requiritur quod haec sit vera ‘Sortes est’ et quod haec sit vera ‘Sorti inest albedo’.” Ockham 1974, p. 281; translation by Freddoso 1980, p. 117. (Summa logicae II, c. 11.) 36 “Notitia intuitiva rei est talis notitia virtute cuius potest sciri utrum res sit vel non, ita quod si res sit, statim intellectus iudicat eam esse et evidenter cognoscat eam esse, nisi forte impediatur propter imperfectionem illius notitiae.” Ockham 1967, p. 31 (Ordinatio I, prol., q. 1). 37 “Similiter, notitia intuitiva est talis quod quando aliquae res cognoscuntur quarum una inhaerit alteri vel una distat loco ab altera vel alio modo se habet ad alteram, statim virtute illius notitiae incomplexae illarum rerum scitur si res inhaeret vel non inhaeret, si distat vel non distat, et sic de aliis veritatibus contingentibus.” Ockham 1967, p. 31 (Ordinatio I, prol., q. 1). 38 “Et primo de propositionibus singularibus de inesse et de presenti et de recto, tam a parte subiecti quam a parte praedicati, et non aequivalentibus propositioni hypotheticae.” Ockham 1974, p. 249; translation by Freddoso 1980, p. 86. (Summa logicae II, c. 2.) 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