What in this case is the condition. Or how would I get a contradiction? E.g. if I said they || A B C D are equidistant, α β γ δ are not equidistant & parallel lines are drawn between them.
     And here Russell's correlation seems to furnish a criterion of their correlatability. A logical criterion.
     Isn't it very queer that by just looking at the names I should be able to say whether or not a certain relation held between the objects?
     But I correlate the names. And why? To see whether a correlation can exist || subsist between the things.
Correlation
Correspondence
We draw lines in our thought.