David:
Your objection so far has been that NSRC is an illegitimate concept because there’s no unifying property that all the referents of NSRC have. In order to counter this claim, I’m going to demonstrate that NSRC has at least one property that SRC doesn’t have. You’ll have to forgive me if this post is a little heavy on the formal logic – I’ve done my best to keep this approachable and I haven’t gone into a formal proof, but it may still be rough if you haven’t taken a math class in a while.
Step One:
Even though concepts aren’t themselves sets, we can introduce a set for each concept such that the set includes everything that the concept refers to. So: (note that upper case letters are concepts and lower case letters are objects)
For the concept “ table ” – T{t1, t2, … tn}
For the concept “ chair ” – C{c1, c2, … cn}
For the concept “ furniture concepts ” – F{T, C, … Concept-n}
For the concept “ concept ” – Concept{T, C, F, … Concept-n}
And so on for any concept…
(If you don’t like the idea of pairing up stuff with sets you can just say that we can make a (theoretical) list of everything the concept refers to. Also, if you don’t like the idea of being able to list all of the objects that a concept will ever refer to, think of this as listing the object it refers to at a past time t.)
Step Two:
For any concept, we can create a “ listing ” of the set that concept corresponds to by removing all of the concepts in the set and replacing those concepts with the elements in their corresponding set. So:
The “listing” of the (set corresponding to the) concept “table” will just be the set that corresponds to table because that set has no concepts in it.
The “listing” of the concept “furniture concepts” will be {t1, t2, c1, c2, … object-n}
The listing of the concept “concept” will be {t1, t2, c1, c2, T, C, … etc}
Step Three:
Note that listing is a process we can perform on any set. Since the listing of a set is itself a set, we can perform a listing on it (assuming that there are still some concepts left in the set). We can continue the process of listing until we’re left with a set containing only object and no concepts – call this a “ full listing ”. We’ll say that concepts which can be given a full listing will be “ fully listable ” concepts.
At this point, then, we can introduce:
Lemma One: Self-Referring concepts are not fully listable.
This should be fairly obvious – if I try to give a listing of a self referring concept I’ll include the concept in my list. When I try to perform a listing on this list I’ll end up including the concept on my new list. When I list again I’ll once again include my concept. I’ll never stop including my concept and so I’ll never end up with a list without any concepts on it – i.e. I’ll never have a full listing.
Lemma Two: Concepts containing no self reference are fully listalbe.
This again strikes me as fairly obvious, but the proof of this claim would be more technical if I were to give it. If you want me to give it, let me know and I will.
Step Four:
At this point we notice something about concepts – some, like the concept of tables and the concept of chairs, are fully listable. Others, like the concept of concepts, are not. We distinguish fully listable concepts from other concepts on this basis and integrate them into the concept of fully listable concepts. We use the symbol CFLC for this concept.
Now, CFLC is either fully listable or it isn’t. If it’s fully listable then it’s referred to by CFLC and, by Lemma 1, CFLC isn’t fully listable. If CFLC is not fully listable then, by Lemmma 2, it is fully listable. Either CFLC is or is not fully listable. Contradiction.
Conclusion:
We’ve seen, then, that a real and legitimate property – the property of being fully listable – will generate Russell’s paradox. I’ve been a little fast and loose with my argument and if anything seems questionable to you I’ll slow down and do the full line of reasoning. Again, the property of being fully listable is a property of the concepts in question – it has nothing to do with a contrast against other concepts.