Flux

Flux is continuous change or movement, especially the view that reality is never wholly static. It contrasts with accounts that treat things as fundamentally fixed.

Heraclitus: An ancient Greek philosopher whose surviving fragments present change and opposition as fundamental features of reality. His river image became the classic expression of reality as flux.
Becoming: The process by which something comes into existence or changes into a different state. Flux describes reality in terms of ongoing becoming rather than completed states.
Substance theory: The metaphysical view that enduring substances are the basic constituents of reality and bear changing properties. It explains change as something that happens to stable things, unlike flux-first accounts.
Process metaphysics: A metaphysical approach that explains reality primarily through events, relations, and processes rather than static entities. It systematizes the claim that flux is more basic than enduring things.
Panta rhei: A Greek phrase meaning “everything flows,” traditionally associated with Heraclitus’s account of change. It condenses the flux associated with Heraclitus into a memorable formula.
Unity of opposites: The idea that opposed forces or properties can be interdependent aspects of a single order. Heraclitus treats tensions between opposites as part of how change holds together.
Being: The condition or nature of existence, treated in philosophy as distinct from becoming and change. Philosophical accounts of being often privilege what remains over what changes.
Whitehead's process philosophy: Alfred North Whitehead’s metaphysical system, in which actual occasions and their relations form the basic reality. Whitehead gives a detailed modern account of a world constituted by ongoing processes.
Parmenides: An ancient Greek philosopher who argued that reality is fundamentally unchanging and that change is illusory. His account directly opposes the Heraclitean emphasis on flux.
Logos: A Greek term for reason, account, or ordering principle, with varied meanings across ancient philosophy. Heraclitus’s flux is not mere disorder; logos names its intelligible order.

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