Assume that the proposition is true. Does this generate a contradiction in every row of the partial truth table? | ||
Yes. Then the proposition is a self-contradiction. | No. Then the proposition is either a tautology or a contingent proposition. Now assume that the proposition is false. Does this generate a contradiction in every row of the partial truth table? | |
Yes. Then the proposition is a tautology. | No. Then the proposition is a contingent proposition. |