I don't get it. Don't "composed" concepts have structure? If not, then I don't understand what you mean by having structure.

Concepts mean lexical concepts. The units are atomic concepts. The structure of 'brown dog' is divided into 'brown' and 'dog'. However, 'brown' itself has no internal-sub-structure. 'dog' itself has no internal-sub-structure, too. Other theories accept the thought that 'brown' or 'dog' has some structures, so they reject the thought that concepts are atomic. For example, some theories of concepts might say that 'dog' is divided into 'animal', 'quadrupedal', 'mammal', and so on. They are positive to accept the structures of concepts, and they are not conceptual atomist positions. Get it?

Doesn't make sense. You must mean concepts can be combined but not decomposed. If concepts can be composed, then they would be composites. So you might be wanting to say that concepts are the atomistic, non-decomposable, units that can then be used to compose.

But atomism is disproven in physics now. And even in language use, it is clear that instead organisation and particularisation are created by contexts of constraint.

The word "dog" limits reference to a class of phenomenon fairly tightly. Talking of the brown dog restricts things even more.

So constraints can be combined reducing the freedom of the possible with any arbitrary degree of precision a situation might require. And there is an atomism of a kind in that composability. But concepts don't have to rigidly possess particular fixed properties as atomism implies. Instead they only need to restrict interpretations, and they don't even have to do that more than loosely much of the time.

I don't get it either. I gather it was a Fodor proposal though I remember the Puttnam talk about how he didn't know an elm from a beech.

What, for instance, is a Labrador? If it's (a) a dog, (b) with certain specifiable features, then it is a concept with, within it, relation between other concepts.

lexical concepts — quine

You'll need to explain what you mean by that.

What you didn't get is what philosophers of concepts usually talk about. Lexical concepts mean simple vocabulary concepts. 'dog', 'brown', 'cat', 'stupid' are lexical concepts. 'brown dog', 'stupid cat' are concepts composed. Most theories of concepts say that lexical concepts have lower levels of contents: for example, 'dog' is divided into 'animal', 'quadrupedal', 'mammal', and so on. Conceptual atomism rejects that concepts (i.e. lexical concepts) have internal structures.

(2) If concepts can be composed, then conceptual atomism is the case. — quine

You haven't shown this. You haven't even shown that concepts can be composed or that they can't be composed under different conceptions of "concept".

The second premise seems problematic. If lexical concepts can be composed of "lower level" concepts, then why must there be any termination to this composition? I don't see why mere composition should imply atomism. You appear to be assuming this, rather than demonstrating it.

Do you not see that 'brown' and 'dog' compose 'brown dog'? Compositionality of concepts is one of the important characteristics of concepts.
What I am defending is that conceptual atomism is necessary for compositionality of concepts.

You misunderstood. I claim that concepts are atomic.

I haven't misunderstood.

The second premise seems problematic. If lexical concepts can be composed of "lower level" concepts, then why must there be any termination to this composition? I don't see why mere composition should imply atomism. You appear to be assuming this, rather than demonstrating it. — Luke

Perhaps the concept "dog" is actually made up of all the atomic conceptions of a dog. We could list a few of these atomic conceptions:

1. The black dog belonging to the butcher with three legs.
2. A poodle
3....

So, let's fabricate a "modus ponens"

1. Concepts are composed
2. If concepts are compositions, conceptual atomism is not the case
3. Therefore conceptual atomism is false.

Anyone convinced?

Do you not see that 'brown' and 'dog' compose 'brown dog'? — quine

No. Do you think "quantum mechanics" and "general relativity" compose to "quantum mechanics general relativity"?

A question:

Is there a set of all atomic concepts?

Your example is not valid one. Of course, 'tuna', 'salad', 'tom' do not compose 'tuna salad tom' conceptually.

That used to be my nick-name at school, to differentiate me from the tom who didn't like tuna salad.

My friend has a nickname called 'quantum mechanics general relativity'.

What you didn't get is — quine

...pretty much everything. The thing is that your argument is so simple structurally that it is either trivial or the real meat of the argument needs some unpacking.

You state that "Most theories of concepts say that lexical concepts have lower levels of contents". And, like you, these other theories also claim that concepts can be composed. Yet they reach the opposite conclusion to you. Why?

Many theories of concepts say that concepts have lower level structures, and that concepts can be composed. Conceptual atomism says that concepts can be composed only when they are atomic.

I'm still intrigued whether there is a set of atomic concepts or not.

Again, I understand this, but you are just asserting conceptual atomism rather than arguing for it.

Again, I understand this, but you are just asserting conceptual atomism rather than arguing for it. — Luke

It is however mildly ironic that the atomic concept of an atom isn't atomic any more.

I did, but you forgot.

What is 'Snoopy'? Is a concept of the fictional dog atomic, or a composition?

'Snoopy' and 'dog' are independent atomic concept respectively.

'Snoopy' and 'dog' are independent atomic concept respectively. — quine

In what sense are either not composed of multiple instances of experience?

You might mean that words, to behave in "the right way" - act like a conjunctive arithmetic - would have to be treated as atomistic particulars ... even when they are actually general umbrella terms. But it is clear that being atomistic is not what word meanings actually are.

You have said both:

"Many theories of concepts say that concepts have lower level structures, and that concepts can be composed. Conceptual atomism says that concepts can be composed only when they are atomic."

"(2) If concepts can be composed, then conceptual atomism is the case."

It's about semantics of concepts. Informational semantics says that meanings of concepts are information.

So what does that mean for your notion of the atomism of concepts. Are they informationally closed or open?

Uttering "dog" is an atomistic act. As a noise we might hear, we know its not someone saying log or bog or dig or dob. But as a concept, dog seems informationally open. We could either generalise or particularise its semantics by adding or subtracting information (or constraints).

Are we talking about a dog or the dog? The Platonically ideal canine, or that little mutt snapping at our ankles?

Atomism kind of works because we can leave the contexual information implied and unsaid. But that doesn't make word interpretations foundationally atomistic. It is of the essence of words that their boundaries of reference are porous or vague. Atomism is relative as semantics is essentially open even if syntax does try to create a closed compositional structure that is meant to keep all the meanings trapped securely inside the spoken sentence.