“Aboutness” is a grand-sounding name for something basically familiar. Books are on topics; portraits are of people; the1812 Overtureconcerns the Battle of Borodino. Aboutness is the relation that meaningful items bear to whatever it is that they areonorofor that theyaddressorconcern.

Aboutness has been studied before. Brentano made it the defining feature of the mental (Brentano 1995). Phenomenologists attempt to pin down the aboutness-features of particular mental states (Husserl 1970). Materialists sometimes claim to have grounded aboutness in natural regularities (Fodor 1987). Medieval grammarians distinguished what we are talking about from what...

Carl Hempel, in whose honor these lectures are given, once wrote of some other lectures, given by Rudolf Carnap at Harvard in the 1930s. Carnap is supposed to have introduced his topic as follows:

LetAbe some physical body, such as a stone, or a tree, or—to borrow an example from Russell—a dog.¹

I wish I could explain my topic the way Carnap explained his, with an example devised by Russell. But I am going to be talking about subject matter, meaning, truth, reasons for truth, contents, parts of contents, extricability of one content from another—as...

A few philosophers have tried to think systematically about subject matter, starting with Gilbert Ryle in his 1933Analysispaper “About” (Ryle 1933). Nelson Goodman tries to improve on Ryle in a 1961 paper of the same name (Goodman 1961).¹ The best and most thorough account to date is David Lewis’s in “Statements Partly about Observation” (Lewis 1988b).²

A sentence is about whatever it mentions, Ryle proposes, where to mention an item k is to contain a word or phrasekthat designates it.³Jones climbed Helvellynis about Jones and Helvellyn, because it containsJonesandHelvellyn. There is...

At this point we know quite a lot. We know for each indicative mood sentenceShow to obtain its subject matter—the one it is exactly about. We know what it takes for one subject matter to include another. The larger subject matter has to refine the smaller one. We know, then, what it means forA’s subject matter to include that of its consequenceB, which is the same asBbeing part ofA. The form of the definition, slightly elaborated from (3) above, is

11Bis part ofAjust if the argumentA, so...

I have been speaking of ways of being true, and sometimes of reasons for truth. The usual term, which I’ll use too, istruthmakers. I will not be trying to tell you “what truthmakers are,” because we can afford to be flexible; it is only their behavior that matters. I allow sentences to be truthmakers. I allow truthmakers that are defined only in particular regions of logical space. I allow truthmaker-makers—reasons, not forAto be true, but for something to be in a position to make it true. I allow truthmakersfortruthmakers. The idea is to present...

Now that we know, more or less, what partial truthis, the question becomes why bother with it? Why make false statements with true bits in them, rather than asserting just the true bits? William James suggests a reason in his debate with Clifford:

a rule of thinking which would absolutely prevent me from acknowledging certain kinds of truth if those kinds of truth were really there, would be an irrational rule. (James 1979, 31–32).

This is usually heard, I assume rightly, as a plea forepistemicboldness. If “acknowledging certain truths” carries a risk of acknowledging the odd...

Inquiry aims at the truth. What is it for one belief state to be closer to the truth than another? There are two dimensions to this. One relates to the kind of attitude we adopt. IfAis true, our attitude toward it should be as close as possible to full belief. The other is to do with the attitude’s content. If thecontentof our belief isA, thenAshould be as truthlike or verisimilar as possible. Confirmation theory is directed at the first goal. The theory of verisimilitude is directed at the other.

Imagine that we are...

If one statement or claim implies another, and the first is clearly true, then one would expect the second to be clearly true, too. Controversy should not erupt between the premises and the conclusion of a valid one-premise argument. And yet sometimes the weaker statement does seem, if not controversial, then at least harder to know than the stronger one. Examples:

(Frege) The number ofFs = the number ofGs. So there are numbers.

(Moore) I have a hand. There are physical objects

(Nozick) I am sitting by the fire. I am not a bodiless BIV.

(Dretske) That...

Once again, it would be nice if I could explain the topic with examples, but we will have to make do with anecdotes. The first concerns a conversation Einstein is supposed to have had with some puzzled citizen.

Citizen: How does the telegraph system work? I don’t see how a message goes down an electric wire.

Einstein: What’s so difficult? Imagine a dog with its head in Moscow and tail in Leningrad. Pull the tail in one place, and the head barks in the other.

Citizen: I’m with you so far, but what about the wireless telegraph? How doesthat...

Who is right about remainders, the mysterian or the logical engineer? The extrapolation model allows a synthesis:Acan always be extrapolated, but not always as far as one might like. It helps to view the matter diagrammatically (see Figure 9.1).

The all-enclosing rectangle is logical space. Truth-conditional contents are regions of that space, containing the worlds where a sentence is true.¹ The proposition thatBis the column on the left, and the proposition thatAis where that column intersects with the horizontal bar. The bar is labeledRto mark it as the remainder whenBis...

A great puzzle of twentieth-century philosophy of language was, how are finite beings able to understand a potential infinity of sentences? The answer is supposed to be that understanding is recursive: infinitely many sentences can be constructed out of finitely many words combined according to finitely many rules; we understand a sentence by understanding the words in it and knowing the relevant rules. If this is right, then meaning, defined as whatever you have to grasp to understand, had better be compositional, too. A sentence’s meaning should be determined by the meanings of the individual words in it and by...

Bear with me as I bring in an unrelated-seeming topic from introductory logic. Students are taught about valid arguments. Validity is a pretty demanding standard, they learn, rarely met outside of logic class. They are not to despair, however, for validity may be achieved by plugging in additional premises. Arguments in need of that kind of completion are calledenthymemes, and plugging the premise in is calledcompletingthe enthymeme. The simplest sort of enthymeme may be depicted as follows:

The problem, in any particular case, is what to put in forR, to make the argument valid. Or rather,...

I want to return now to the comparison begun in section 10.4 between piggybacking on a game and pivoting on a presupposition. The two have a lot in common, we said.Acan take on different figurative contents, for instance, as we vary the game, and different incremental contents as we vary the presupposition. Could it be that pivoting and piggybacking are one and the same phenomenon, or inessential variants of each other? This was rejected on the following grounds (repeated from chapter 10).

If the contentAacquires through pivoting onBisA–B, then pivoting can only...