Verifying method of the values of truth or falsity of the statements of the logic propositional, consisting of the combination of all values of truth and falsity of propositions to determine the final values of statements that can be tautologies or laws, if all values are true; contradictions, if all are false and indeterminations, if some true and the other false. Is, for example, the statement p or not p; as it is a statement of order one, as there is a single proposition, the combination will be two values: true - false and false - true, that by the definition of the disjunction will give us true in both cases. It is the beginning of third excluded: to be or not to be, that is the question.
