One of the largest works of Abu Nasr Al -Farabi and the greatest singing for those interested in studying Arab thought in general and Islamic philosophy and the jurisprudence of the Arabic language in particular, wrote it before the logic in an era in which Arab thought reached aspects of understanding matters of science and language, and the necessity of the correct expression of what a person considers and rationalize. It is not dispensed with reading those who work in the history of philosophy and language.