Philosophical anthropology is the philosophical study of human nature. In terms of learning, examples of descriptive theories of the learner are: a mind, soul, and spirit capable of emulating the Absolute Mind (Idealism); an orderly, sensing, and rational being capable of understanding the world of things (Realism), a rational being with a soul modeled after God and who comes to know God through reason and revelation (Neo-Thomism), an evolving and active being capable of interacting with the environment (Pragmatism), a fundamentally free and individual being who is capable of being authentic through the making of and taking responsibility for choices (Existentialism).[21] Philosophical concepts for the process of education include Bildung and paideia.