 Famously obscure, accused by Plato of incoherence and by Aristotle of denying the law of non-contradiction, Heraclitus writes in an aphoristic style. His apparently paradoxical claims present difficulties to any interpreter. Nevertheless, he raises important questions about knowledge and the nature of the world. The opening of Heraclitus’ book refers to a “logos which holds  forever.”[3]  There is disagreement about exactly what Heraclitus meant by using the term logos, but it is clear from DK22B1/LM9D1, D110, and R86 and DKB2/LM9D2 as well as DKB50/LMD46 and other fragments that he refers to an objective law-like principle that governs the cosmos, and which it is possible (but difficult) for humans to come to understand. There is a single order that directs all things (“all things are one” DKB50/LMD46); this order is divine, and is sometimes connected by humans with the traditional gods (it is “both unwilling and willing to be called by the name of Zeus” DKB32/LMD45). Just as Zeus, in the traditional view, controls everything from Olympus with a thunderbolt, so this single ordered system also steers and controls the whole cosmos, but from within. The sign of the unchanging order of the eternal system is fire—just as fire is always changing and always the same, the logos, itself permanent, contains the unchanging account that explains the alterations and transformations of the cosmos.