The soul, in many religious, philosophical and mythological traditions, is the incorporeal and, in many conceptions, immortal essence of a living thing. According to most of the Abrahamic religions, immortal souls belong only to human beings. For example, the Catholic theologian Thomas Aquinas attributed "soul" (anima) to all organisms but argued that only human souls are immortal. Other religions (most notably Jainism and Hinduism) teach that all biological organisms have souls, and others teach that even non-biological entities (such as rivers and mountains) possess souls. This latter belief is called animism.Greek philosophers such as Socrates, Plato and Aristotle understood the psyche (ψυχή) to be crowned with the logical faculty, the exercise of which was the most divine of human actions. At his defense trial, Socrates even summarized his teachings as nothing other than an exhortation for his fellow Athenians to excel in matters of the psyche since all bodily goods are dependent on such excellence (The Apology 30a–b).Anima mundi is the concept of a "world soul".