Through the process that Heraclitus undertakes to understand the world around him he fundamentally and yet, abstractly adheres his thinking to principles which govern the world. Heraclitus advocated for the doctrine of flux, the coincidence of opposites, and that fire is the source and nature of all things.
(B54) “An unapparent connection (harmonia) is stronger than an apparent one.”
Everything is in flux- in the sense that “everything is always flowing in some respects,” (B49a) “We step into and we do not step into the same rivers. We are and we are not.”
Coincidence of opposites- interpreted as the view that “every pair of contraries is somewhere coinstantiated; and every object coinstantiates at least one pair of contraries.” The coincidence of opposites, entails contradictions, which Heraclitus cannot avoid. On this view Heraclitus is influenced by the prior theory of material monism and by empirical observations that tend to support flux and the coincidence of opposites.
(B8) What is opposed brings together; the finest harmony [harmonia] is composed of things at variance, and everything comes to be [or, “occurs”] in accordance with strife.
(B67) “God is day and night, winter and summer, war and peace, satiety and hunger, but changes the way when mingled with perfumes, is named according to the scent of each.”
Unchanging principle- the logos- that both governs and explains these changes. The physical sign of the logos is fire: always changing yet always the same.” (p. 40)
(B43) “Willful violence [hubris] must be quenched more than a