Template:Individual-TLP-paragraph-en-5.513

5.513 We could say: What is common to all symbols, which assert both p and q, is the proposition “p . q”. What is common to all symbols, which assert either p or q, is the proposition “p ∨ q”.

And similarly we can say: Two propositions are opposed to one another when they have nothing in common with one another; and every proposition has only one negative, because there is only one proposition which lies altogether outside it.

Thus in Russell’s notation also it appears evident that “q : p ∨ ~p” says the same as “q”; that “p ∨ ~p” says nothing.