Nowadays, one of the most important discussions in modal logic and analytic metaphysics is the distinction between de dicto and de re modalities. For example one of the basic foundation of accepting essentialism is acceptance of de re necessity. This essay points to the history of this distinction in Islamic and Western Philosophy, and then deals with syntactical and semantical difference between these two kinds of modality, and compares this distinction with two similar distinctions, and finally looks at relationship of de dicto and de re modalities.

The notion of "possible worlds" apparently raised by Leibnitz for the first time, is recently put into account for the role it plays in the semantics of modal logic. The most significant theories on possible worlds are categorized into two general types,i.e.actualism and possiblilism about each of which there are various versions. In this survey, the versions of D.Lewis and kripke on possiblilismm and those of R.Stalnaker, R.Chisolm, R.Adams, and A.Plantinga on actualism are examined and criticized.

The history of religious and rational thought has entertained many ideas concerning the arguments for the existence of God. Among the arguments advanced, there have been three kinds of arguments known as: teleological, ontological and cosmological arguments; and Alvin Plantinga can be named as a great figure who has added to these three kinds the forth. Indeed, his endeavors are to be esteemed as a new argument for the existence of God. The argument is by the name of "epistemological argument of proper function for the existence of God". This essay, considering Plantinga' s view on epistemology of beliefs, is to show the reader the premises of the argument and to assay its efficiency. The author holds that the argument in question, although is seriously dependent on the "theory of proper function" of warrant, is a new way in establishing the existence of God and can be considered as good path, upon which a rational believer can rely      

From long time ago, simplicity of Divine Essence was hold by many philosophers and theologian of great religions such as Christianity and Islam. On one hand, in Islamic tradition, philosophers like Ibn Sina and Mullah Sadra, and on the other hand, in Christian tradition, theologians like Augustine and Anselm and especially Aquinas attempted to strengthen the substructure of this doctrine and to explain various aspects of it. One important aspect of this doctrine, with which the present essay deals, is the sameness of God’s essence and his real attributes such as knowledge and power. This aspect of the doctrine has been recently criticized by some contemporary philosophers of religion like Alvin Plantinga. Reviewing the viewpoints of the proponents of the doctrine in the two Islamic and Christian traditions, the essay presents a more accurate articulation of Aquinas’ viewpoint. Then, it examines the foundation of Plantinga’s criticisms. And finally, it shows that these criticisms have been raised in a paradigm quite different from that of classical philosophers, and thus they may not produce any difficulty for the above-mentioned doctrine when considered in the paradigm of classical philosophy.

The purpose of this paper is firstly, to defend the evidentialist approach to the rationality of beliefs, secondly, to examine the evidentialist challenge to the rationality of religious beliefs, and thirdly, to survey Plantinga's approach to the challenge. In this paper, I will argue that the evidentialist challenge is flawed; however, the evidentialism is defensible. So, Plantinga's project to refute evidentialism is not perfect, because he does not need to have a position against evidentialism to establish the rationality of belief in God, rather he may accept evidentialism and at the same time to refute the challenge by means of a complementary account of evidentialism.In this paper it will be shown that we can develop the concept of evidence to include private evidence as well, because evidence is not restricted to the propositional evidence or public evidence. Furthermore, I will argue that in spite of basicality of belief in God, the theistic beliefs still need the discriminating evidence in some contexts. Accordingly, a new concept of evidentialism will be offered for religious beliefs to be rationally justified.

One of the most important issues in philosophy of religion is religious diversity. Different view points have been offered in the encounter of the religious diversity from philosophers of religion. The purpose of this research is to examine and compare Alvin Plantinga`s theory as an exclusivist view and Allameh Tabatabaee`s theory concerning religious diversity. Allameh Tabatabaee by presenting the inclusivist view believes that all religions benefit from truth and savior, but Islam considered well-known to seal of religions, is more perfect than others. His most significant argument to support the inclusivist view is that the divine widen salvation requires all human beings in different culture and religions save. While Alvin Plantinga, by exclusivist attitude maintains that only one religion can be true and only its followers can be saved. He believes that truth and salvation is based on Christian's doctrines and teachings and considered Christianity as justified religion.

Alvin Plantinga believes there are some kinds of conflicts between some deliverances of science and religious beliefs. To correct, on one hand, misinterpretations of the Scripture and, on the other hand, wrong scientific claims, he proposes, we must use in science all of what we know: what we find through experience, as well as what we know by way of faith. Methodological naturalism, one of methodological assumptions of scientific practice, prevents us to achieve this goal. According to methodological naturalism, scientists can’t use supernatural explanation, evidence and concept in science. In addition to rejecting methodological naturalism, Plantinga maintains many theories in humanities apply normative concepts and definitions; and religion can be used as a source for this concepts and definitions. Consequently, Plantinga’s idea, Augustinian Science, has been based on four principles: using hermeneutical finding along with empirical evidence in science; rejecting methodological naturalism; using normative concepts and definitions which comes from religious world view, in theories which need them; assuming properly basic beliefs of believers.