Footnote zz1

zz1. On monadism, The Internet Encyclopedia of Philosophy:

Together with several apparently self-evident principles (such as the principle of sufficient reason, the law of contradiction, and the identity of indiscernibles), Leibniz uses his predicate-in-subject theory of truth to develop a remarkable philosophical system that provides an intricate and thorough account of reality. Ultimately, Leibniz's universe contains only God and non-composite, immaterial, soul-like entities called "monads." Strictly speaking, space, time, causation, material objects, among other things, are all illusions (at least as normally conceived). However, these illusions are well-founded on and explained by the true nature of the universe at its fundamental level. For example, Leibniz argues that things seem to cause one another because God ordained a pre-established harmony among everything in the universe. Furthermore, as consequences of his metaphysics, Leibniz proposes solutions to several deep philosophical problems, such as the problem of free will, the problem of evil, and the nature of space and time. One thus finds Leibniz developing intriguing arguments for several philosophical positions—including theism, compatibilism, and idealism.

On monadism, Britannica:

The concept is intimately connected with Aristotle’s distinction between matter and form, or the potential and the actual. He analyzed each thing into the stuff or elements of which it is composed and the form which makes it what it is (see hylomorphism). The mere stuff or matter is not yet the real thing; it needs a certain form or essence or function to complete it. Matter and form, however, are never separated; they can only be distinguished. Thus, in the case of a living organism, for example, the sheer matter of the organism (viewed only as a synthesis of inorganic substances) can be distinguished from a certain form or function or inner activity, without which it would not be a living organism at all; and this “soul” or “vital function” is what Aristotle in his De anima [Latin title of the Greek work; On the Soul in English] called the entelechy (or first entelechy) of the living organism. Similarly, rational activity is what makes a man to be a man and distinguishes him from a brute animal." Leibniz...called his monads (the ultimate reality of material beings) entelechies in virtue of their inner self-determined activity. The term was revived around the turn of the 20th century by Hans Driesch, a German biologist and philosopher, in connection with his vitalistic biology to denote an internal perfecting principle which, he supposed, exists in all living organisms.

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