Leibniz: Life and Main Philosophical Ideas

Biographical Background

Gottfried Wilhelm Leibniz lived from 1646 to 1716. He was a German philosopher, mathematician, jurist, diplomat, and polymath. He independently developed calculus, designed calculating machines, and wrote on logic, theology, history, and language. Much of his philosophy appears in essays and correspondence rather than one single systematic book.

Major works include Discourse on Metaphysics, Monadology, Theodicy, and New Essays on Human Understanding.

Philosophical Thought

Leibniz's metaphysics centers on monads. A monad is a simple, non-material, indivisible substance with inner activity. Extended material things can be divided, so they cannot be ultimate substances. Reality is grounded in simple centers of perception and appetite.

Monads do not causally interact. Each unfolds according to its own internal principle. The apparent harmony among them is explained by pre-established harmony: God created all monads so that their inner developments correspond perfectly, like synchronized clocks.

Leibniz formulated the principle of sufficient reason: nothing happens without a sufficient reason why it is so rather than otherwise. He also defended the identity of indiscernibles: if two things have all the same properties, they are not two things but one.

He distinguished truths of reason and truths of fact. Truths of reason are necessary; their denial is contradictory. Truths of fact are contingent but still have sufficient reasons, ultimately grounded in God's choice of this world.

Leibniz's theodicy argues that this is the best of all possible worlds. This does not mean every event is good in isolation. It means that God chose the world with the greatest overall balance of order, richness, and goodness. Voltaire famously mocked this idea, but the philosophical problem remains serious.

Leibniz also dreamed of a universal symbolic language and a calculus of reasoning. This anticipates later developments in logic and computation.

Leibniz's importance lies in his vision of reality as rationally ordered, infinitely rich, and composed of unique individual perspectives reflecting the whole.