1 Brentano on intentional inexistence

Brentano makes a case for the claim that the distinctive feature of mental phenomena is what he calls intentional inexistence. Later on, other philosophers called this feature intentionality.

Brentano starts by illustrating the kind of phenomena that he is interested in describing: judging, recollecting, doubting, believing are mental phenomena, as are emotions and feelings. According to Brentano, every mental phenomenon is either a presentation of something or is based upon some such presentation.

By a presentation, Brentano means something the act of presenting something, like hearing a sound or seeing a color. Brentano’s notion of presentation is closely related to what he calls intentional inexistence. By the latter, he just means “reference to an object, direction towards a content". He elaborates:

Brentano briefly discusses whether a phenomenon like pain also has this feature. It doesn’t seem that pain is about anything, or presents something, or is directed towards a content.

Still, this is compatible with the claim that only mental phenomena exhibit intentionality, even if not all do. This can still allow us to say that what is distinctive of the class of mental phenomena is that they are directed towards something, or that they have intentionality.

Despite its vagueness, Brentano’s discussion of intentionality as the distinctive feature of mental phenomena has been influential. We will examine an attempt by Roderick Chisholm to sharpen the notion, and see how far it can get us.

2 Chisholm on intentional inexistence

Chisholm aims to refine Brentano’s thesis and see if an attitude like assuming or accepting is one of the attitudes characterized by intentional inexistence. Above we said that intentional inexistence was a kind of directedness. Chisholm identifies one of the main features of intentional inexistence as follows:

For instance, think about an attitude like believing that the music festival in Brooklyn next week will be awesome, or wanting to ride a unicorn. Someone can have these attitudes even if there won’t be any music festival in Brooklyn and even if unicorns don’t exist. Compare the sentences used to describe attitudes with the following: ‘Aristotle sat on a tack’, ‘Soccer balls are usually white’. If the first sentence is true, it entails that there are tacks, and if the second is true, it entails that there are soccer balls. We will call the first kind of sentences intensional (with an ‘s’).

The kind of sentences that we use to describe attitudes and the sentences that describe other kinds of facts are syntactically the same. When I say ‘I’m looking for the nicest unicorn’ and ‘I sat on a tack’, the two sentences seem merely to describe relations between me and something else. The first one seems to describe a relation between me and the nicest unicorn, and the second one seems to describe a relation between me and a tack. The difference between the two is that in order for the first one to be true, the object of the relation need not exist, but in the other one it must. We may say that the first one is intentionally related to (or directed towards) something that doesn’t exist.

Chisholm refines this notion by describing three features that characterize intensional sentences:

(i)

A non-compound declarative sentence is intensional if it uses a substantival expression in such a way that neither the sentence nor its negation implies that there is or that there isn’t anything that the referential expression stands for. E.g. ‘I believe that unicorns are pretty’ implies neither that there are unicorns nor that there aren’t, which is why this sentence is intensional.

(ii)

A non-compound sentence with a propositional clause (a clause whose content is a proposition) is intensional if neither the sentence nor its contradiction implies either that the proposition in the clause is true or that it is false. E.g. ‘I imagine that she killed the dragon’ implies neither that she killed the dragon nor that she didn’t; compare with ‘She succeeded in killing the dragon’, which implies that she killed the dragon.

(iii)

Suppose that there are two names ‘x’ and ‘y’ which designate the same thing. If E is the sentence ‘x is identical with y’, A is a sentence in which ‘x’ occurs, and B is a sentence identical to A, except for the fact that, wherever ‘x’ occurs in A, ‘y’ occurs in B. Then A is intensional if the conjunction of A and E doesn’t imply B.¹

A compound sentence (one obtained by joining sentences with sentential connectives) is intensional just in case at least one of its component sentences is intensional. Some of our uses of perception-expressions are intentnional in the sense above.

Now we can present Brentano’s thesis as follows: (a) we do not need to use intensional sentences in order to fully describe non-psychological phenomena, but (b) when describing psychological attitudes we must use sentences that are either intensional or use terms we don’t need to use when describing non-psychological phenomena.²

Chisholm examines three ways to disprove Brentano’s thesis, but he doesn’t find them satisfactory.

3 Linguistic behavior

One strategy to get rid of intensional sentences is by means of translations of these sentences into sentences merely about behavior. Chisholm considers and dismisses one such translation: A man believes that there are unicorns if he is disposed to utter sentences containing words that designate or refer to unicorns.

It’s easy to see that this won’t do, since ‘designate’ and ‘refer to’ seem to give rise to intensional sentences themselves. For instance, the sentence ‘In German, the word Einhorn designates, or refers to, unicorns’ does not entail that unicorns exist or that unicorns don’t exist. We may attempt to define designation of reference in terms of intensions, but it doesn’t look like this will do it either. One way to try to define intensions is this: The intension of a predicate ‘Q’ for a speaker X is the general condition which an object y must fulfill in order for X to be willing to ascribe the predicate ‘Q’ to y. But the same kinds of problems arise from ‘ascription’.

Let us now suppose that we define ascription thus: a person X ascribes ‘Q’ to an object y, provided that in the presence of y, X gives an affirmative response to the question ‘Q?’ This won’t do either, for people can make mistakes, and so, it may be that Anna sees a fox from afar and is presented with the question ‘Dog?’ to which she answers affirmatively. Thus, when we combine this definition of ascription with our definition of intension above, we obtain the result that at least that particular fox fulfills the condition determined by Anna’s use of the word ‘Dog’, but this is the wrong result.

Would it help if we assume that Anna is usually right when she takes something to be a dog? Not really, for we may assume that the occasion above is the only one in which Anna has seen a fox, and so, we must say, falsely, that the fox doesn’t fulfill the condition determined by the intension of ‘fox’, as used by Anna.

There is no obvious way to fix the notion of intention appropriately.

4 Sign behavior

Some people have suggested the following:

How should we define this signifying relation? Many people have appealed to substitute stimulus. According to such definitions, the sign is described as a substitute for the referent:

Problem: how to sharply specify the similarity conditions?

5 Attempting to define expectation

Here’s a way of defining expectation without intensional terms. S expects E to occur means that S is in a bodily state b such that either (i) b would be fulfilled if and only if E were to occur or (ii) b would be disrupted if and only if E were not to occur.

But even this may be seen to fail, unless we use intentional terms. See p. 489. What if someone meets his aunt and takes her to be someone else? In this case, the fulfillment and satisfaction conditions wouldn’t occur in the manner required by the definition.