Leibniz’s Solution to the Mind-Body Problem

The aim of philosophy, according to Leibniz, is to explain how God does things, “how things are brought about by the Divine Wisdom in conformity with the particular concept of the subject.”[1] In his Discourse on Metaphysics, he already establishes that each substance’s nature already contains all the predicates[2] and is like a “mirror” of all that is in the universe.[3] Leibniz explicitly assumes that God is the creator of all things and the universe – He is the “architect of the machine of the universe,”[4] and being omniscient, knows all the predicates contained in each thing including the future, which is hence predetermined.

Image by John Hain from Pixabay

Each substance is acting in its own “sphere”[5] but yet there seems to be an “appearance”[6] of communication between things. For instance, when ball A hits ball B on a billiard table, it seems to cause ball B to move, even though based on Leibniz’s metaphysics, both balls are independent, each doing what it does because it is already predetermined in its nature rather than because of a causal interaction with each other. Leibniz attempts to explain how this is possible in his article, A New System of the Nature and the Communication of Substances. He then builds on this theory to explain the mind-body problem, or how can an immaterial soul and a material body of a person interact.

Leibniz’s Solution to the Problem of Evil

Leibniz believes that God is omniscient. An omniscient god would know everything about his creations including the future, which is hence predetermined. Leibniz then has to explain how evil, which is seen everywhere in the world, is possible under such a perfect God.