Is/Ought Problem according to Allameh Mesbah Yazdi

One of the most perplexing problems in the epistemology of Ethics is the "Is/ought problem." This conundrum stems from a passage in David Hume's A Treatise of Human Nature, where he observes, "In every system of morality … I am surprised to find, that instead of the usual of propositions, is and is not, I meet with no proposition that is not connected with an ought or an ought not. This change is imperceptible; but is, however, of the last consequence. For as this ought, or ought not, expresses some new relation or affirmation... This small attention would subvert all the vulgar systems of morality... ." (Hume, A Treatise of Human Nature, p.۲۱۵) As a result, this problem has come to be called "Hume's Law" or "Hume's Guillotine." It has also been referred to by many other names, such as the Is/Ought distinction, Is/Ought Split, Is/Ought fallacy, Is/Ought gap, Is/Ought dichotomy, Is/Ought controversy, Is/Ought thesis, Is/Ought relation, Is/Ought separation, Is/Ought divide, Is/Ought alienation, Is/Ought impasse, Is/Ought gulf, Is/Ought fallacy, naturalistic fallacy, fact/value problem, and more. It is important to note that Hume's paragraph has been interpreted in different ways. Some have taken it to imply that "Ethics" arises from "Emotion" rather than "Reason," while others believe that "Ought" cannot be deduced from "Is." The second interpretation is the prevailing one and has proven to be a significant challenge in the epistemology of ethics and law. Indeed, many philosophers, such as Hume in the current interpretation, contend that we cannot deduce "Ought" from "Is." John Searle and others hold a different view on the Is/Ought problem compared to Professor Allameh Mesbah Yazdi. It is worth noting that Professor Yazdi put forward the "Derivational Theory," which argues that we can derive "Ought" from "Is." According to this theory, "Ought" sometimes represents "Objective Necessity," which can be grasped through "Comparative Necessity." This provides a powerful solution to the Is/Ought problem. The present study aimed to explore this theory using a comparative and analytic approach. We will argue that the Is/Ought problem stems from the mistaken belief that "Ought" always signifies a prescriptive (normative) sentence, which naturally contradicts a declarative one. However, this is not the case because "Ought" can refer to "Comparative Necessity" in reality. Professor Mesbah believed that when there is a complete cause, the existence of an effect is comparatively necessary. This type of necessity can be apprehended through comparison. Therefore, if a sentence describes this kind of necessity, it should be a declarative sentence. According to Islamic philosophical terminology, there are three types of necessity: Necessity by itself, necessity by something else, and necessity in relation to something else (comparative necessity). Professor Mesbah's theory states that real values are derived from facts and can be comprehended through comparative necessity between value acts and their ultimate purposes. The use of the word "Real" here implies that some values come from actual facts that are connected to Allah (God) as the foundation of all real values.

Keywords:

Is-ought problem , ethics , Is/ought gap , Hume's guillotine , Is/ought fallacy , Allameh Mesbah Yazdi