“The Methodological Role of the Principle of Nothing Proceeds from the One but the One” is the title of an article the writer of which believes that the explanation of this principle is limited to a number of problems in the field of metaphysics in its particular sense. Therefore, any reference to it “in order to demonstrate logical and natural problems and some problems in metaphysics in its general sense” is unjustified. In this paper, in response to the above claim, the writer shows: 1) this idea was initially proposed by Mulla Sadra and later evaluated and developed by Hakim Sabziwari (although the article mentioned above refers to Mulla Sadra’s view and Sabziwari’s evaluation and development of this view, it does not provide any response to it); 2) the origin of this view neglects the limit of modal unity; 3) all through this article the true One is mixed with the one truth; 4) in the mentioned article, the original principle and its opposite are intermingled, and the claim of the original principle also effects its opposite, and 5) the writer of the same article considers the “impossibility of inferring a single concept from multiple referents” to be one example of the false applications of the principle of “Nothing proceeds from the One but the One”, whereas philosophers have not resorted to this principle in this regard. It seems that this error originates in equating the relationship between the concept and the referent with causality. Even if we assume that it is correct, it is better to say that this problem is based on the opposite of this principle rather than its original form. However, the claim made in the article, if assumed correct, entails the original principle and not its opposite. Moreover, the mentioned problem is not even based on the opposite of the principle.