The concept of efficient causation originates with Aristotle, who states that the types of cause include ‘the primary source of the change or rest’. For Medieval Aristotelians, the scope of efficient causality includes creative acts. The Islamic philosopher Avicenna is an important contributor to this conceptual change. In his Metaphysics, Avicenna defines the efficient cause or agent as that which gives being to something distinct from itself. As previous studies of Avicenna's ‘metaphysical’ conception of the efficient cause attest, it takes (...) God as a model agent. This essay considers whether Avicenna's ‘metaphysical’ conception of the efficient cause applies to natural agents. It ultimately argues that Avicenna offers a unified view of the efficient cause, which includes both divine and natural agents. On this view, an efficient cause gives being to another and is simultaneous with its effect. While Avicenna's defence of this view is an important chapter in the history of the concept of the efficient cause, it is also of interest in its own right. By appeal to a version of the principle of sufficient reason, it challenges a widespread view that causes are temporally prior to their effects. (shrink)

Neither Aristotle nor Aquinas assumes the reality of the evolution of species. Their systems of thought, however, remain open to the new data, offering an essential contribution to the ongoing debate between scientific, philosophical, and theological aspects of the theory of evolution. After discussing some key issues of substance metaphysics in its encounter with the theory of evolution (hylomorphism, transformism of species, teleology, chance, the principle of proportionate causation), I present a Thomistic response to its major hypotheses. Concerning the philosophy (...) of Aquinas, I trace what might be seen as a preliminary description of natural selection in his commentary on Aristotle's Physics. Turning toward theology, besides addressing the topics that were referred to in the past—such as: Aquinas’ reading of Genesis, his account of creation as dependence in being, secondary and instrumental causality, and univocal/equivocal predication of God—I bring into discussion Thomas’ concept of the perfection of the universe, which has been virtually unused in this context. (shrink)