According to Muslim philosophers, what distinguishes human soul from that of animal are theoretical and practical reason. But there is more than one interpretation of theoretical and practical reason among these philosophers and sometimes even in the works of a single philosopher.The paper aims at clarifying the meaning of practical reason from the viewpoint of Avicenna (ibn -Sina).Referring to Avicenna's works four terms and expressions as to the practical reason can be identified. In some of these expressions, the practical reason has only the function of conceiving general or particular practical propositions. In some others, it has, besides conceptual function, a practical one. Examining these four expressions, it becomes clear that none of them comes in accord with the two expressions prevalent among Muslim philosophers. The article ends with an attempt to bring back the four expressions to a single comprehensive one.

"reason", hikmat, philosophy, knowledge, and psychic faculty, are divided, in Greek philosophy, into theoretical and practical ones. Muslim philosophers diverge on the nature and function of these two types of reason. Some of them consider them of the same nature, i.e. comprehension and reasoning. According to them, the difference lies in the fact that the object of first one is knowledge, and that of the second one is action. Still some others put the burden of both on theoretical reason. Some philosophers consider theoretical reason an instance of cognition and practical reason an instance of action, and they deem their cooperation as leading to a mixture of knowledge and action.According to the common view, practical reason gets to particular knowledge by deliberating on theoretical understandings, so that it can guide psychic powers to action. Theoretical reason enables one to understand facts, while practical reason guides one to manage one's personal, as well as social, affairs. The author thinks that it is "heart", and not practical reason, that motivates one toward a set of actions.

This article employs an analytical-descriptive and, to a certain extent, a comparative methodology to examine the prominent views of Muslim philosophers regarding practical reason and its origins as rooted in Aristotle's works. Then, a novel explanation of Avicenna's opinion regarding the cognitive or stimulating nature of practical reason based on his principles of psychology is presented and briefly contrasted with Farabi's opinion. The role of practical reason in Avicennian ethics is subsequently examined in light of the dual meanings of practical wisdom in his works. The findings of this study indicate that Avicenna, based on his foundations in the separation of faculties, never attributed a single action to two faculties in an essential and primary manner. Consequently, the perception of reasonable generalities is an essential act of theoretical reason, and the perception of particulars is an essential act of the animal soul's faculties. Therefore, Avicenna does not consider practical reason to be a cognitive faculty. The essential act of practical reason is the inference of the beauty or ugliness, and goodness or badness of partial acts as evidenced by perceptual faculties. This function of practical reason has a negative preliminary role for practical wisdom as science and a positive, stimulating role for practical wisdom as a virtue. However, one should not overlook the other significant function of practical reason in producing moral propositions generally accepted by the common people.

The relation between Ethics and social phenomena could be studding by investigating the roots of professional Ethics in social sciences. This article tries to define professional Ethics by focusing on it under a social theory. The separation between "morals of professions and their laws" and "Ethics and professions as universal law of ethics in all humanistic professions" actually is separation between two kinds of norms in social institutions. Although the first set is generally called professional Ethics but those are norms of social groups and the second emphasize at entering the common moral values of human in all professions. In the works of Emile Durkheim we can see the first functions of this explanation. He deduces the concept of professional Ethics from the theory of mechanic and organic solidarity. In this theory, Ethics is outcome from society. But practical wisdom in Islamic philosophy is the base of Ethics. practical wisdom by the rational law of goodness issues the universal law of Ethics and by the other side of wisdom which is called strategic reason could overcome the ambiguity of the explanation of professional ethics.

From the viewpoint of different theories of social and human sciences, the position/role of reason in science is not the same. By considering the constituents of social and human sciences, as expressed in the theories of human sciences, and by considering the limits and realm of reason, as expressed in the theories of reason, we can evaluate the position/role of reason in each of the submited images of social and human sciences. Part of this extensive research is to assess the validity of the various images of these sciences based on the limits and realms accepted for practical reason in theories of reason. This article seeks to examine the rationality of social and human sciences using this various images presented by theories of reason. The method of this study is to analyze the theories of social and human sciences in order to assess the position/role of practical reason in each of these theories. For this purpose, using some theories of human sciences, various components involved in the realization of human sciences are identified. Then, using theories of practical reason, different probabilities of the limits and realm of practical reason are expressed. Finally, according to different probabilities concerning the limits and realm of practical reason, the position/role of practical reason in the theories of the humanities, which have been analyzed, is revealed.

The functions of practical reason are briefly and excursively discussed in the books discussing the principles of jurisprudence. Although many commands of practical reason are used in the principles of jurisprudence, both the major commands – such as the rule of rational badness and goodness - and the minor commands – such as the badness of Tajarri (daring against God), the badness of wasting God's purposes, and the goodness of precaution, but this subject is not separately and elaborately discussed in any one of these books. Some aspects of this subject are discussed in some precedent books; for example the discussion of goodness and badness is discussed in these books: 'Al-Fava'ed Al-Ha'eriyyah' (refer to Vahid Behbahani, 1415 LAH, pp. 363-378), 'Al-Fosoul Al-Qaraviyyah' (refer to Saheb Fosool, 1404 LAH, pp. 316-350), 'Fara'ed Al-Osool' (refer to Sheikh Ansari, pp. 230-245) and 'Hedayah Al-Mostarshedin' (refer to Mohaqqeq Isfahani, pp. 433-442). But in the books of recent scholars this little discussion is also rarely found; it is only Isfahani (Mohaqqeq Isfahani, 1374 SAH, v. 2, p. 322 on) who has mentioned this discussion while he presents the reasons of Insidad (lack of religious sources). Martyr Sadr has also mentioned this discussion in his different books to some extent; and recently one of his pupils, Abu Raqif, has presented an independent discussion regarding the applications of practical reason in the principles of jurisprudence in a two volumed book named 'Al-Osas Al-Aqliah'. It is clear that these discussions should not be discussed in the principles of jurisprudence rather they should be discussed in the philosophy of the principles of jurisprudence; and this science, like the philosophy of other sciences, has not been completely developed in religious fields. Yet some worthy scholars have made great efforts in this regard and have tried to establish these sciences.* After explaining the meaning of expressions of this subject and the meaning of practical reason and clarifying the subject and its range, the functions of practical reason in the principles of jurisprudence will be explained in this article.

Mulla Sadra believes there are effective interactions between reason and ethics which have different funnctions. The source of human acts is practical reason which provoks the soul to use its practical facaulties for doing the particular acts. This matter depends on the ideas and beliefs which are apeared in the dimension of pure reason. by understanding the particular goodness and evil in practical reason dimension the acts have been chosen and issued as a virtue. According to the level of perception, the soul originates the specific acts. As the soul has various perceptions including sensual, imaginary and rational, accordingly, the acts and their proper virues will be issued. He holds that by rising the reason, two important attributes that is, justice and freedom will be manifested for the soul which transcends the soul facaulties and by managing the corporeal passions, the soul comes to be free from all chains. The justice and liberty originates all human virtues. At this research, the relationship between pure and practical reason and moral behaviors has been analyzed and shown that there are mutual nexus between the immateriality of the perceptions and ethics.

Since Ethics is one of the subdivisions of practical wisdom, Islamic philosopher’s view point is very important in explanation of theoretical and practical reason.This paper is going to analyze the distinction between practical and theoretical reason from Haeri’s point of view. In order to finding the roots of his issue, at the beginning we will propose the idea of philosophers like Farabi, Ibn Sina, Qotb- al- din Razi, Mulla Sadra and Sabzevari; then we will have a review on Haeri’s view and his interpretation of Ibn Sina’s one.With finding and highlighting of contradictions and differences in Ib Sina’s view point, He tries to resolve the antinomies undermining in his ideas about distinction between practical and theoretical reason. He also stands against the view of some thinkers, such as Qotb- al-Din Razi, and some Asuliyyin like Mozaffar, and challenges their ideas.According to his philosophical views, Haery also explicates the distinction between propositions of practical and theoretical reason. Moreover, he tries to clarify the meaning of the word ‘reason’ and show that how theoretical reason converts to practical.

there have been several views by Muslim scholars on the quiddity of theoretical and practical reason and how they function in the understanding of practical sentences. One view considers theoretical reason; the understanding of the basis of all general theories, including theoretical and practical reasons, and practical reason considers the principle of partial practical and also determinants of action (Ibn Sian’ s view). The other view considers the theoretical reason only as the understanding of the theoretical sentences and considers the practical reason as the understanding of the general and partial practical sentences and considers as the instigator the act’ s doing. (Al-Tusi’ s view and al-Ghazali in Maqasid al-Falasifa). The third view considers theoretical reason as both the theoretical and the general and partial practical sentences, and considers the practical reason to be the sole agent of action and the temptation of it. (Bahmanyar’ s view, Qutb al-Din al-Razi, and al-Ghazali’ s in Miar al-Elm). The present article, by explaining the angles of these three perspectives and analyzing the speeches in this regard, argues that the right view is the second view and that the practical reason is two kinds. One deals with generalities, which is the equivalent of theoretical reason, but understands general practical understanding. Another deals with details that understand both the practical details and how to do and deal with them.

One may say that The Open Society and Its Enemies (OS) offered in 1945 the first complete elaboration of the general approach proposed by Karl Popper, namely his ‘critical rationalism’, a bold generalization of the fallibilist falsificationism in the domain of the empirical sciences masterly proposed in Logik der Forschung (1934). The political content of The OS has been critically discussed. Nevertheless, not all people insist on the equally important moral dimension of the book, giving it its unity, I submit. Without morality, no critical discussion, no reason, no open society, let us say in a nutshell. I would argue that according to Popper, a strictly Christian morality of love would not be the appropriate emotional companion of critical rationalism, but that the less demanding moral emotion of sympathy or compassion is perhaps necessary to give it its force against violence. I give some support to this line of argument. In my view, Popper proposed a somewhat unarticulated critical rationalist ‘emotivism’ of sorts. The emotion of compassion is necessary for triggering our moral decisions and values, which are the ultimate basis of the choice for a reason against violence.