Pierre Hadot

“All Hellenistic schools seem to define [wisdom] in approximately the same terms: first and foremost, as a state of perfect peace of mind. From this viewpoint, philosophy appears as a remedy for human worries, anguish, and misery brought about, for the Cynics, by social constraints and conventions; for the Epicureans, by the quest for false pleasures; for the Stoics, by the pursuit of pleasure and egoistic self-interest; and for the Skeptics, by false opinions. Whether or not they laid claim to the Socratic heritage, all Hellenistic philosophers agreed with Socrates that human beings are plunged in misery, anguish, and evil because they exist in ignorance. Evil is to be found not within things, but in the value judgments with people bring to bear upon things. People can therefore be cured of their ills only if they are persuaded to change their value judgments, and in this sense all these philosophies wanted to be therapeutic.”
― Pierre Hadot, What Is Ancient Philosophy?

“It is not things that trouble us,” as Epictetus said, “but our judgment about things,”
― Pierre Hadot, The Inner Citadel: The Meditations of Marcus Aurelius