metaphysics

metaphysics the branch of philosophy that deals with the first principles of things, including abstract concepts such as being, knowing, substance, cause, identity, time, and space. Metaphysics has two main strands: that which holds that what exists lies beyond experience (as argued by Plato), and that which holds that objects of experience constitute the only reality (as argued by Kant, the logical positivists, and Hume). Metaphysics has also concerned itself with a discussion of whether what exists is made of one substance or many, and whether what exists is inevitable or driven by chance.

Recorded from the mid 16th century, the word represents medieval Latin metaphysica (neuter plural), based on Greek ta meta ta phusika ‘the things after the Physics’, referring to the sequence of Aristotle's works: the title came to denote the branch of study treated in the books, later interpreted as meaning ‘the science of things transcending what is physical or natural’.