Therefore...

Therefore, knowledge which is capable of truth—that is, which corresponds to reality—and is capable of error—that is, which differs from reality—that very knowledge is acquired knowledge. And if truth is attributed to knowledge by presence, this is in the sense of a denial of the possibility of its being in error.

Meanwhile, the definition of truth, which is discussed under the topic of the value of knowledge, is known, that is, it is the correspondence of the form of knowledge with the reality which it describes.

However, there may be other definitions of truth, such as the definition of the pragmatists, “Truth is a thought which is useful in the practical life of man,” or the definition of the relativists, “Truth is knowledge which is appropriate to a healthy perceptual apparatus,” or a third definition, which says, “Truth is that upon which all people agree,” or a fourth definition, which says, “Truth is knowledge which can be proved by sensory experience.” All of these are besides the point of the discussion, and avoid answering the original problem about the value of knowledge.

They can be considered as signs of the inability of the definers to solve this problem. Supposing that some of them are correctly justified, or they are considered as the definitions necessary for specific cases (even if the definition itself is not correct), that is, they are considered as specific signs of some truth, or they indicate some specific terminology, but in any case, it must be noted that none of these justifications are able to solve our original problem.

The question about the truth in the sense of knowledge which corresponds to reality is left unanswered, and requires a correct and clarifying answer. Criteria for the Recognition of the Truth The rationalists hold that the standard for recognizing the truth is ‘the nature of the intellect’ ( fiṭrat-e ‘aql ).

The propositions which are inferred correctly from self-evident propositions and which are really components of them are considered to be truth, while sensory and experiential propositions are considered valid to the extent that they are proved by the aid of intellectual arguments.

However, we do not see any explanation given by them of the correspondence of self-evident propositions and innate propositions ( fiṭriyyāt ) with realities, except the one mentioned by Descartes, who resorted to the wisdom and honesty of God with respect to innate thoughts.