The concept of meaning is recalcitrant to analysis, elucidation, or theory. There is almost no consensus about what constitutes meaning. We possess the concept, but we don’t know what to say about it—it is opaque to us. Thus we are treated to a wide variety of opposed suggestions: mental images, dispositions to behavior, truth conditions, verification conditions, criteria, possible worlds, functions, intentions, use, modes of presentation, mental models, nothing at all. Compare the concept of knowledge: there is wide agreement that knowledge is a type of true belief. Granted, there are differences of opinion, especially when it comes to filling out the idea of true belief, but the involvement of truth and belief are not contested. Our concept of knowledge makes this clear to us; it is not a complete cipher. But the concept of meaning is silent about itself, or speaks with many voices. We don’t know what it entails. We search for a central concept with which to understand it, say the concept of truth, but soon encounter difficulties with sentences that are not truth-bearers (imperatives, questions, exclamations, performatives, ejaculations), among other difficulties. In the case of knowledge the concept of truth is clearly central, but in the case of meaning it is only disputably so—hardly a necessary condition of meaning.
Why does the concept of meaning contrast so strikingly with the concept of knowledge? They are both concepts we possess, yet one is relatively transparent and the other maddeningly opaque. Indeed, it is hard to think of a concept of philosophical interest that is quite as opaque as the concept of meaning—quite as fundamentally contentious. Take belief, intention, necessity, causation, truth, free will, and consciousness: at least there is some consensus here—all is not darkness. People know what they are talking about, more or less. Why then is meaning so obscure, elusive, and slippery? Take the locution “x knows that s means that p”: we know what “know” means in this type of sentence, but when it comes to “means” we are brought up short. Thus we have a meta-puzzle about the puzzle of meaning: the puzzle of why is it so puzzling? Why is the puzzle a puzzle? It ought not to be, given that the concept is very familiar to us, but apparently it is. What is the concept of meaning such that it is puzzling in the way it is? Phonetics and syntax are not similarly puzzling, so why is semantics so up in the air? Why is the theory of meaning such a quagmire? Wittgenstein veered sharply from a truth conditions theory in the Tractatus to a use “theory” in the Investigations: how did the concept of meaning make that possible? How could it give rise to such contradictory intimations?
The question has not been asked, so far as I know, but possible answers suggest themselves. It might be said that the word “meaning” is ambiguous: the reason no single central concept carries the day is that the word signifies quite different things. Likewise, there is no satisfactory theory of banks, if we insist on supposing that “bank” is univocal: x is a bank if and only if x is a river with money floating in it! When we say “Snow is white” has meaning in the same sense that “Shut the door!” has meaning we speak erroneously; rather, these two types of sentence mean in different senses. I don’t know of anyone who has ever propounded such an ambiguity thesis, but it is surely implausible in the extreme, for reasons too obvious to be worth going into. More plausible is the idea that “meaning” is a family resemblance term, so that the search for a single definition of meaning is misguided. Some meanings are constituted by truth conditions and some by verification conditions, while some have their meaning by dint of use, or the association of mental images. Thus the different theories that have been proposed are correct for some varieties of meaning but not for all; we have here the familiar philosophical vice of overgeneralization. Again, I don’t know that anyone has ever held this view—certainly not Wittgenstein in the form just described (he held that all meaning is use). Or again, it might be suggested that “meaning” is an empty term and the concept of meaning a pseudo-concept: that’s why we can’t come up with an adequate theory of it. There is nothing for the theory of meaning to be a theory of, so the wheels are turning in a vacuum. How can there be agreement about the content of a concept that has no determinate content? This account of the puzzle is also hard to swallow: words and sentences certainly seem to mean something, even if we find it hard to say what this consists in. But there does seem to be something in the idea that the concept is exceptional in some way—that it is a concept of a certain type—and that this type precludes it from the usual kind of analytic treatment. It is a concept that belongs in a different category from the concept of knowledge and similar concepts. We are mistaking the category and then cudgeling our brains over how it should be analyzed. Let’s pursue this hint.
The dictionary is always a useful point of departure. The OED gives this definition for “meaning”: “what is meant by a word, text, concept, or action”. The broad scope of the word “meaning” is registered here, though the definition looks disappointingly circular, what with the word “meant” occurring in it. However, the definition does offer the suggestion that meaning should be understood in the context of what is meant by agents—those who utter words, write texts, possess concepts, and perform actions. For x to have meaning is for x to be meant in a certain way by agents. Presumably, this relation is a type of action or process or event; so what has meaning is what is usable to mean something in such acts, etc. But what is it for an agent to mean something? The dictionary doesn’t say, but we can: it is to employ a symbol in order to communicate—to get something across, to convey something to somebody. This is a highly neutral description with nothing specific contained in it—nothing about truth or verification or images or dispositions or criteria or use. Meaning is simply what is meant when people communicate. This could include gestures and facial expressions (“She gave him a meaning look”) as well as elements of grammar or signs of arithmetic. Notice that there is no requirement for all the things that can be meant to resemble each other, either by sharing a common property or by dint of family resemblance. There need not be anything in virtue of which the class of things that can be meant mean what they do; the class is united merely by its relation to agents. So, in particular, the class is not united by the property of having truth conditions or verification conditions, but merely by being usable in a certain way, i.e. to get something across. This is not to say that meaning is use in the manner of Wittgenstein; it is just to say that meaning is a matter of getting things across by employing some kind of symbolic entity or other. This isn’t a theory of meaning, just an indication of its scope and context. The question of interest here is whether this definition of “meaning” resolves our puzzle.
Consider the concept of furniture. The OED defines “furniture” as “the movable articles that are used to make a room or building suitable for living or working in, such as tables, chairs, or desks”. Notice that this is not a family resemblance concept: there is no suggestion that all items of furniture have any such resemblance. Rather, the class of items is determined by the use the items are put to, supplemented with some examples. We could call it a functional concept, except that would align it with the concept of biological function. I prefer to call it a “collectivity concept” because it gathers together a widely heterogeneous collection of items according to how they are used (“suitable for living”). It would obviously be a mistake to try to define this class by fastening onto certain of its members, as if the shape of chairs (say) could define it. This would give rise to pointless controversies as other theorists select a different subset of furniture items (beds, say, instead of chairs). It is not that furniture has a hidden essence not apparent on the surface to be discovered by empirical methods. Furniture has no nature beyond what the dictionary definition specifies. It is not like water or heat—or even knowledge. Nor is the concept elusive or obscure, though it may be vague and interest-relative. Well, the concept of meaning is like that—a collectivity concept held together by what agents mean (strive to communicate). There is no property with a submerged nature that we might investigate and articulate. Items with meaning might well have properties with such natures—such as truth conditions or verification conditions—but these properties are not what meaning in general is. There are no identity statements of the form “Meaning is X”, where X might be truth conditions or verification conditions (or use, etc.). There are many properties in virtue of which an item can be meaningful, but none of these is what meaning is. There are many properties in virtue of which an item can be an instance of furniture, but none of these is what being furniture is (e.g. being shaped to fit the human body). I will put this point by saying that the concept of meaning is a collectivity concept not a property concept, acknowledging the inadequacy of these portmanteau terms. The intuitive idea is that meaning is not a single attribute common to all meaningful items but what items come to have when agents use them to get things across.
The point of this proposal is to explain why the theory of meaning takes the form that it does. We are taking a concept of one type and assuming that it is of another type—a category error. We search for a single central concept because we assume that meaning is a property that meaningful items have—like the property of knowledge. It is true that meaning involves various properties, such as truth conditions, but it involves many properties, so that it cannot be united by any one of them. So there cannot really be a theory of meaning, i.e. a specification of what all meaningful items have in common (including use). The concept of meaning is not the concept of any property or trait of the sort proposed by putative theories of meaning, just as the concept of furniture is not the concept of any property or trait of items of furniture such as comfort or human shape or intentional design or location in the home. We tend to think the concept belongs to the same category as the concept of knowledge or belief or intention, which do have a uniform nature, but in fact, it is like the concept of furniture or tool, whose principle of unity is quite different. In effect, we are reifying the concept—taking it to connote something over and above using a symbol to get something across. Asking the question, “What is meaning?” or “What does meaning consist in?” invites the kind of category error I am diagnosing. Better to ask, “In virtue of what does this act of meaning work?” Then we can specify what property is being exploited in the act of meaning, such as truth conditions, verification conditions, felicity conditions, intensions, extensions, images, conventional use, etc. It is not that the word “meaning” is ambiguous between these various properties, any more than “furniture” is ambiguous between chairs and beds; rather, these words connote collections of things united by patterns of human employment, namely in living and communicating. There cannot therefore be a general theory of meaning of the kind that people have sought. To be specific, the idea that meaning is truth conditions is a category mistake. There can be theories of truth conditions (like Tarski’s theory of truth) but there cannot be theories of meaning, not because they are false and some other type of theory is true, but because it is misguided to seek theories of meaning to begin with. So it isn’t that the concept of meaning is maddeningly opaque but rather that we misconstrue what kind of concept it is. Semantics isn’t so controversial because the concept of meaning has a content that we can’t easily access; rather, it’s because the concept has no such content, being what I am calling a collectivity concept. This resolves the puzzle.
 Much the same point can be made about the meaning of individual words: names have meaning and so predicates, but there doesn’t have to be anything else they have in common that makes them usable in acts of communication, such as a denotation. There is no theory of meaning common to names and predicates, only the fact that both compose sentences that can be used to communicate, i.e. be meant in a certain way. It would be a mistake to cudgel our brains in the search for the common semantic property possessed by different categories of expression (compare chair legs and chair seats).
 In a sense the position defended here is more Wittgensteinian than Wittgenstein. He took language and meaning to be family resemblance concepts, assuming genuine resemblance, and opposed this to a common essence view. I am suggesting a view on which there is no resemblance at all between different meaningful items, but only a similarity of employment. We can thus allow that there is nothing remotely alike about facial expressions and sentences–not sound, not grammar, not truth conditions—and yet both count as meaningful items. All we can say to unite them is that both can be used to get things across. Contrast members of a family and people who happen to do the same job: the former look alike, but not the latter. So meaning is even more heterogeneous and unsystematic than Wittgenstein supposed.