“The thunderbolt pilots all things” (K 119; DK D64)
“The thunderbolt steers the totality of things” (Robinson)
Compare Fragment 54: “The wise is one, knowing the plan by which it steers all things through all.”
The thunderbolt is known in the Greek world as Zeus’ tool. Heraclitus’ metaphysics, while dismissive of the traditional teachings of the gods of Hesiod, naturalizes the functions of the gods. The wise one, as he says in K 118, “is and is not willing to be spoken of by the name of Zeus.” Rational law, the logos, at least metaphorically able to be taken as God’s directives, guides the universe.
The Stoics interpret Heraclitus here as deterministic. Everything is fated by the laws of nature. But this stands in some tension with Heraclitus’ moral teaching. “Man’s character is his fate” he famously says in Fragment 114 (D119). These and his injunctions to care for the moral law of the city, for example, seem to indicate a realm of freedom amidst the law-guided cosmos.
The reference to a “plan” through which all things are steered highlights again teleology. Knowledge is achieved through knowledge of the laws of the cosmos that direct things towards their ends.