The popular notion of truth is that it is the actual state of affairs, whether known or not, whether tested or not. But until a specific state of affairs is asserted, we cannot test and confirm that it is true. So to say truth can be unstated and therefore untested leaves the word truth pointing vaguely into the unknown.

For an assertion to be tested and found to be truth, it must be spoken or written. This may seem an innocent requirement, but it carries a heavy implication:  truth is a product of language.

To establish an assertion as true, we must have an accepted method for evaluating assertions, but this does not restrict the establishment of truth to the methods of logic. In Handling Truth, four traditional methods for evaluating the truth of assertions are recognized: debate, faith, logic, and research. While you or I may accept or reject any of these methods, we must recognize that others may accept the methods we reject–and reject the methods we accept.

It may be unsettling to think that truth relies on the rules of a testing method, but the truth we find depends on the test we select; if we use two different testing methods (e.g. faith and scientific research), we will find contradictory truths. And when we do, we can only reject the findings of one of the two methods, or live with dissonance.

—William Melvin Gardner–