“The following may be set down in a general manner as his main principles: that everything is created from fire, and is dissolved into fire; that everything happens according to destiny, and that all existing things are harmonized, and made to agree together by opposite tendencies; and that all things are full of souls and dæmones. He also discussed all the passions which exist in the world, and used also to contend that the sun was of that precise magnitude of which he appears to be. One of his sayings too was, that no one, by whatever road he might travel, could ever possibly find out the boundaries of the soul, so deeply hidden are the principles which regulate it. He used also to call opinion the sacred disease; and to say that eye-sight was often deceived.” — Diogenes Laertius, *Lives of Eminent Philosophers*, Book IX, *Life of Heraclitus*, VI (trans. C. D. Yonge, 1853) **Surface Gloss:** The cosmos is saturated with souls and intermediary *dæmones*, while the human soul itself has no discoverable spatial boundary because its governing principle is unfathomably deep; ordinary human opinion is a form of epilepsy. **Opinion as Cognitive Epilepsy**: Treat unexamined certainty ("opinion") not as a minor intellectual error, but as a seizure that severs the mind from shared reality. Conversely, treat the mind's capacity for structural insight as non-local and boundless: you never hit the "edge" of understanding by digging deeper into the governing principles of a problem, only by stopping at surface impressions.
— In our words · Source: Lives of Eminent Philosophers (Diogenes Laertius)