Meta-ethics deals with conceptual and confirmatory principles. In part, it deals with issues related to deduction of moral statements, such as the relation among moral statements and the relation between moral and non-moral statements. According to Martyr Mutahhari the fact that moral statements are demonstrable is among logical meta-ethical questions that are seldom treated. Explaining Mutahhari's opinion on the demonstrability of moral statements, the author says that Mutahhari intended to prove that moral statements produce certainty. Contrary to what appears from some analysis of his words, he intended to say that moral statements are rational. Albeit in his Methodology of Realism, he explains AllamaTabatabaei's words on the indemonstrability of moral statements in five ways, he however rejects all these five explanations in his Perpetuity of Moral Principles, considering some moral statements as self-evident truths of practical reason, which are, in turnendorsed by theoretical reason as well.