 The logic operation of negation closely resembles not in natural language. It is used in propositional logic to construct compound propositions with the opposite truth value of that of the simple proposition on which it operates. Negation is thus a unary that is a single argument logical connective and it is symbolized by a specific not symbol or by the symbol called tilde. Let's illustrate this operation using the example Brutus killed Caesar. Applying our standard knowledge about the world, we can assume that this proposition is true and that not P, that is Brutus did not kill Caesar, is then false. And vice versa, if P is false, that is Brutus did not kill Caesar, then not P, Brutus killed Caesar, can be concluded to be true. Thus negation is interpreted intuitively as being true when P is false and false when P is true.