The faults and inconsistencies found in semantics have undermined the place of this scientific field in literary studies and its importance in understanding the beauty of the texts and its capacity in analysis of literary issues. These faults often arise from lack of scientific method and clear definition of the principles of semantics. The aim of this research is to review, critique and explain 'omission and mention', which is one of the major questions of semantics. ‘Mention and omission’ are among the most important rhetoric tools of the Persian poets and writers variously and repeatedly used over the course of literary history. Therefore, its explanation along with the analysis of its rhetorical effects has been at the center of attention since the early periods