Still, that’s not ‘twoness’. That’s a sentence that’s only satisfied when there are two things, and could be taken as a definition of what it means to assert that there are two things, or even as a definition of there being two such things, but it’s not ‘twoness’. ‘Twoness’ implies number is a property of objects, which I think Frege pretty conclusively disproved.
I think the fact that a definition of “2” in symbolic logic can be taken to count as an answer to the question “What is twoness, physically?” pretty much says all that needs to be said about the clarity of the question.
There are two dots, but that’s not “twoness”. Otherwise, we wouldn’t be able to count distant objects that are never in conjugation, or ideas.
∃x∃y ( ~(x=y) & ( ∀z ( ~(z=x) ⊃ (z=y) ) & ( ~(z=y) ⊃ (z=x) ) )
Only works in a limited universe of discourse, though.
In lower brow discourse, try: (.)v(.)
I think you may have meant (.Y.)
That works too. Although I must confess I prefer the smaller cup size. :P
Or ∃x∃y ( ~(x=y) & ∀z ( z=y or z=x) )
Still, that’s not ‘twoness’. That’s a sentence that’s only satisfied when there are two things, and could be taken as a definition of what it means to assert that there are two things, or even as a definition of there being two such things, but it’s not ‘twoness’. ‘Twoness’ implies number is a property of objects, which I think Frege pretty conclusively disproved.
I think the fact that a definition of “2” in symbolic logic can be taken to count as an answer to the question “What is twoness, physically?” pretty much says all that needs to be said about the clarity of the question.