How do you define what is true and be extension what is reality.

There is a general agreement among scholars that truth is a property of statements (propositions). However, it is notoriously difficult to provide an informative account of the concept “truth”. I presented three of the most popular theories of truth, namely, the Correspondence theory, the Coherence theory, and the Pragmatic theory.

The Correspondence theory maintains that propositions are true by virtue of their correspondence to the objective reality. For example, the proposition “There is a book on the table.” would be true if there is a mind-independent reality of objects in which there is a table with a book on the table. This position is very appealing to many people because it reflects most of our pre-philosophical intuitions on the matter. However, there are two main problems for the correspondence theory of truth.
First, the relation of correspondence between mental entities (beliefs, statements, propositions) and the objective reality raises a lot of concerns. Reality is presented to us in our mental states. Thus, everything that people consider “objective” has an essential subjective component. If we do not have an independent access to one element of the correspondence relation, then the relation begins to appear vague and mysterious.
Second, there are many propositions that are considered true without any obvious relation of correspondence. For example, the truths of mathematics, logic, and ethics do not seem to correspond to anything objective. Thus, the correspondence theory is at best incomplete because of its inability to account for the status of abstract truths.

The Coherence theory of truth has emerged as an alternative to the correspondence theory. The Coherence theory maintains that the truth of a proposition is its relation of coherence with a previously accepted set of beliefs. A set of coherent beliefs should be understood as a self-sustained system of compatible beliefs. The coherence theory is able to explain more than the correspondence theory and it does not rely on the problematic appeal to a mind-independent reality. The biggest problem for the coherence theory is the charge that it makes truth relative to an individual. Since most people believe that they posses a set of coherent beliefs, then their beliefs will meet the coherence criterion of truth. However, it seems very counter-intuitive that there are so many sets of true beliefs.

The Pragmatic theory of truth takes a radical approach to the problem. The pragmatists maintain that the concerns of the Correspondence and the Coherence theories are very scholastic. As an alternative, the pragmatists suggest a new criterion of truth, namely, the positive practical significance of a belief. Thus, according to the pragmatic theory, a belief is true if it makes a positive impact on a person’s life. This seems to be an easy and convenient way to identify true beliefs but it leads to two main problems. First, it seems clear that some false beliefs can make a positive difference in a person’s life. Second, it seems that the pragmatists got things backwards. The pragmatist would say that a belief is true because it makes a positive impact on a person’s life but it would be easier to argue that a belief makes a positive impact because it is true. The Pragmatic account of truth may be appealing to many people but it comes with very serious theoretical problems.

In order to underscore the need for a good account of truth, I introduced the so-called Paradox of the Liar. What is the truth value of the following statement?

“The statement expressed by this sentence is false.”

If this self-referring statement is true, then it would have to be false and if it is false, then it would have to be true. A good theory of truth should be able to eliminate or explain away the above paradox.