What is reality made of?

The first answer: everything is ultimately one substance — water.

Not water but the 'boundless' (apeiron) — an indefinite source beyond any single element.

Responding toThales

Reality is not a stuff but a process: everything flows, unified only by the Logos.

By pure reason, change is impossible: Being is one, eternal, and unchanging; the senses deceive us.

Responding toHeraclitus

Saves the many: reality is atoms moving in the void — nothing but particles and empty space.

Responding toParmenides

The truly real is not physical at all: eternal Forms, grasped by reason, of which the visible world is only a shadow.

Responding toHeraclitus and Parmenides

Brings the Forms down to earth: real things are matter shaped by form; no separate realm is needed.

Responding toPlato

All reality emanates from a single ineffable source — the One — and everything longs to return to it.

Responding toPlato

Distinguishes essence from existence: in everything but God, that a thing is differs from what it is.

God is Being itself (ipsum esse); creatures merely receive their existence.

Responding toAvicenna

There is only one substance — God or Nature — of which all particular things are modes.

Responding toDescartes' many substances

Reality is infinitely many simple, mind-like substances — monads — coordinated by pre-established harmony.

Responding toSpinoza

There is no matter at all: to be is to be perceived; only minds and their ideas exist.

Responding toLocke's material world

We can never know things-in-themselves — only the world as structured by our own minds (phenomena).

Responding tothe whole dispute

Absolute Idealism: reality is the self-unfolding of rational Spirit; 'the rational is the actual', known fully only as a whole.

Responding toKant's unknowable thing-in-itself

Reframes the question entirely: not 'what things exist' but what it means 'to be' at all — the forgotten question of Being.

Responding tothe whole metaphysical tradition