One of the ways to understand the nature of any science is through knowing its constitutive components. Practical wisdom, in the position of a demonstrative science, possesses three components: subject matter, problems, and principles. Knowledge of these components facilitates a better understanding of this discipline. The present study focuses on the nature of the principles of practical wisdom and their relation to the subject matter and problems of this science from the perspective of al-Fārābī, one of the leading philosophers engaged in the discourse on practical wisdom. The aim is to obtain a clear picture of the foundations for proving the issues of this discipline and through this inquiry, the characteristics and nature of practical wisdom itself as well as the the manner of constructive engagement with it, are likewise clarified. By analyzing and explicating al-Fārābī’s statements, the study seeks to clarify the meaning and function of the components of science and their interrelations. It further elucidates the notion of the conceptual and judgmental principles of practical wisdom, their divisions, and the manner in which these principles contribute to the demonstration of the problems of practical wisdom. In addition, attention is devoted to distinguishing the judgmental principles of practical wisdom from generally accepted propositions (mashhūrāt), which function as judgmental principles in dialectical sciences. The study also examines the role of mashhūrāt in the two domains of the emergence of practical wisdom, culture-building, education, and moral discipline of members of society in accordance with the teachings of this wisdom.