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.