I think it's cool that you looked into Brandom. I've put a fair amount of time into his work, but of course I've only used a few key concepts of his, for my own purposes. I don't feel constrained by my influences, naturally.

such beetles are necessary, but lie beyond the aperspectival limitations of social norms and communication. — sime

To me private concepts is an oxymoron, but I'm open to something like a continuum. Philosophers try impose upon current norms, usually by appealing to norms which are not currently being challenged. They want an eccentric candidate inference or world-disclosing metaphor to become widely recognized. If one thinks concepts get their meanings from claims, then concept modification will often involve using familiar concepts in new inferences, thereby mutating the concepts. We also have an expressive enough language to talk about concepts directly, and such claims might be accepted as explication (obvious upon hearing, etc.)

I personally avoid talking about 'pure' or 'internal' meaningstuff which is contained in expressions. I suggest that equivalence classes of expressions are a nice alternative to the idea of this meaningstuff. Different sentences can be used for pretty much the same purpose, so they have the same meaning (as use). Eccentric uses are advertised and defended by philosophers for admission as standard uses.

Some hold that idiolects in this sense do not exist or that the notion is useless or incoherent, but are nonetheless happy to use the word “idiolect” to describe a person’s partial grasp of, or their pattern of deviance from, a language that is irreducibly social in nature.

I'm happy with the bold part. In fact that's probably all of us as individuals. But we push toward a center. The philosopher as such manifests a truthbringing intention. I'm not sure that's the best way to put it, but there's a motive, a push, a project. It is deeply social, essentially outward and self-transcending.

Just as a coherent self is an infinite task, so is the community's co-articulation of the world.

Here's Brandom on Hegel:

Hegel denies the intelligibility of the idea of a set of determinate concepts (that is, the ground-level concepts we apply in empirical and practical judgment) that is ultimately adequate in the sense that by correctly applying those concepts one will never be led to commitments that are incompatible according to the contents of those concepts. This claim about the inprinciple instability of determinate concepts, the way in which they must collectively incorporate the forces that demand their alteration and further development, is the radically new form Hegel gives to the idea of the conceptual inexhaustibility of sensuous immediacy. Not only is there no fore-ordained “end of history” as far as ordinary concept-application in our cognitive and practical deliberations is concerned, the very idea that such a thing makes sense is for Hegel a relic of thinking according to metacategories of Verstand rather than of Vernunft.

All that he thinks the system of logical concepts he has uncovered and expounded does for us is let us continue to do out in the open, in the full light of self-conscious explicitness that lets us say what we are doing, what we have been doing all along without being able to say what was implicit in those doings.

meaning that concepts only exist in the minds of the individuals making up the public body — RussellA

Concepts don't exist in the head. They exist in the movements of the body, including the movements of mouth and hand and all the [ other kinds of ] action that claims are used to justify, explain, predict.

This is one of the problems with indirect realism. It's dualist ! You are trapped in your head. But I say we perform conceptuality, primarily in the time dimension, for we are the timebinding primate. What Hegel calls Geist ('spirit') is just complicated patterns in the Nature from which it emerged. What is called consciousness is, in my opinion, better understood as the being of the world for a [discursive] self. A 'conscious' person sees the world and not immaterial meanings and sensations, etc.

To me anyway that makes more sense, but I didn't start here.

Personally I wouldn't put beliefs 'in the mind. — plaque flag

If my belief that it will rain tomorrow isn't in my mind, how can I know that this is my belief.

Do you see claims through your sense organs ? I think not. — plaque flag

The first claim being that simple ideas come into the mind in the form of nonpropositional awarenesses
The second claim being that these ideas once in the mind somehow get converted into something that can stand in inferential relations to propositions in the mind

As regards claim one, true. I can see many things without knowing its name.
As regards claim two, partly true. Some things I see I do know its name.

If my belief that it will rain tomorrow isn't in my mind, how can I know that this is my belief. — RussellA

Now that you mention it, I think beliefs would largely (maybe usually ) function inferentially in the usual way of folk psychology. A guy on LSD jumps off a building, because (we speculate) he believed he could fly --even without articulating that belief. But we articulate in our attempt to explain.
Note that we attribute beliefs to dogs and cats too.

If you claimed to believe P, people could still argue you were lying. You might fear that you are lying to yourself. Or you could be very confident, say it out loud, etc. So it's a rich issue.

As regards claim two, partly true. Some things I see I do know its name. — RussellA

What is needed is claims, propositions, premises --- though classification will often lead in that direction.

Concepts don't exist in the head. They exist in the movements of the body, including the movements of mouth and hand and all the [ other kinds of ] action that claims are used to justify, explain, predict. — plaque flag

Where in my body is my concept of open government.

This is one of the problems with indirect realism. It's dualist ! You are trapped in your head — plaque flag

If trapped in my head, how have I managed to survive X years in a harsh, brutal and unforgiving world.

Where in my body is my concept of open government. — RussellA

Look in the dimension of time.

Can you summarize that concept in a sentence ?

Imagine a photograph taken of a dancer. It's just a frozen pose and not the dance. We are the most intensely temporal creatures we are aware of.

If trapped in my head, how have I managed to survive X years in a harsh, brutal and unforgiving world. — RussellA

That's why (I claim) you aren't trapped in your head with immaterial meanings and imaginary apples. [ Or at least I argue for direct realism. ]

Booo! More infighting and misunderstanding! :D

I think I'm tracking -- you're not a dualist in terms of substance or properties. Maybe a simpler way to put it: some entities which we speak about exist, and some entities which we speak about don't.

And upon coming to find out strange things like the dress, or the various other phenomena which have been mentioned to point out a difference in individual experience, one has a reason to doubt that our experience is like what we thought it was before, whatever that may have been.

My question to the Direct Realist is, if all observers are directly observing the same facts in the external world, then why do different observers make different judgements about the moment when one fact changes into a different fact. — RussellA

Because they're seeing different parts.

Suppose our senses are represented by a circle on a plane -- everything inside the circle is our mental-bodily-insides, and the outside surface of the circle is our sensual limit. This is a world defined by shape, line, space, and relative position. As the surface conforms to other geometric shapes we'll get a different description. In fact, one would actually have to be me the same circle to get the exact same description. But because all reality is perspectival, an unfolding surface, that's impossible. I'm tempted to claim that a phenomenological direct realism predicts that we'll see things differently, but that's not right either (because if it were a transcendental phenomenology, it'd be the opposite)

For me the inferential plane is just a metaphor that emphasizes that all entities (angels, attitudes, anvils, aardvarks) have meaning in the first place because they are related to other entities (keeping in my the semantic basis of the proposition in which concepts embedded). I can claim that repressed terror causes toothaches. I can claim that god caused the world. Whether or not the claim is plausible or accepted is secondary here to its meaning. Note that God can be the highest entity in terms of status and still be just on the plane in terms of the interdependent semantics I'm trying to make explicit.

All roads lead to Rome, and all concepts and claims lead back to the inferential philosophical-practical situation. In more practical situations, I explain my actions by giving reasons. Here on the forum, it's almost entirely about justifying or explicating claims.