Abstract

According to a common definition, the argument of truthful ones is an argument in which the existence of Necessary Being is proved with no presumption of the existence of the possible being. Avicenna proposed different versions of this style of argument and the version in the book of Nejat is one of them. This paper is intended to examine the possibility of proving the logical validity of this version in first-order predicate logic and explain the principles which the argument is based on. In this way, it becomes clear to what extent Avicenna's version is in accordance with the criteria he himself introduces for the argument of truthful ones. In this respect, while providing a clear exposition of the version in the book of Nejat, bugs on some of the statements and proposals to obviate them in terms of replacement arises. Then explaining the concepts and premises which the argument in the book of Nejat is besed on, it is formulated in first-order predicate logic with its full proof. Finally, the proposed model's accordance with the presented criteria for the argument of truthful ones will be shown.