Language is the best human communication tool invented by man, as a person cannot communicate with members of his linguistic community without it or with non-linguistic signs. The question that arises is whether the linguistic sign that a person uses has the ability to name the things around him in the external world. Therefore, our research came to clarify the relationship between the linguistic sign and the truth, according to the theories and ideas that were presented by jurisprudence scholars. We also tried to present our vision in the field, especially by presenting examples of that. Among these examples are people with mental illnesses who have lost the correct use of vocabulary and that the linguistic sign is insufficient to match the linguistic sign with the thing. As a result of this situation, the language also loses its social function, as in poetry when it is first heard For a poetic poem.