A dispute · spans 5 eras
Being vs. Becoming
Is reality fundamentally stable, or fundamentally in motion?
The oldest argument in philosophy. Parmenides argued that what truly is must be one, whole, eternal, and unchanging – change is contradictory and our senses are lying. Heraclitus argued the opposite: reality is process, change is the only stable thing, and stability is just temporary form. The stakes are knowledge itself: if everything flows, knowledge has nothing to grip; if nothing ever changes, the entire visible world is a deception. Plato sided with Parmenides (the Forms are unchanging), Aristotle tried to do justice to both, modern physics has tilted toward Heraclitus, and Hegel's whole philosophy is in some sense Heraclitus winning the argument 2,400 years later.
// The sides
Being
Whatever truly is must be one and changeless; change is a logical contradiction, and the senses that report it deceive.
Becoming
Reality is process through and through: ceaseless change is the one constant, and all stability is only a passing shape of the flux.
Both
There are changeless forms and principles, yet they operate precisely within things that come to be and pass away in time.