Stoicism

In ethics, Stoics saw themselves as perpetuating the key ideas of Socrates (c. 470–399 B.C.E.), especially as presented in Plato's (c. 428–348 or 347 B.C.E.) dialogues. These ideas were combined with the view of philosophy as an integrated system of branches of knowledge and a picture of reality as an intelligible and unified whole. For the Stoics, complete wisdom consisted in a synthesis of ethics, physics (study of nature), and logic.

The Stoic ethical ideas drawn from Socrates were that virtue was unified, a type of knowledge, and the only thing that was good in itself. Also Socratic were the ideas that virtue was the sole basis for happiness and that all human beings were capable of achieving full virtue. The Stoics developed these ideas into a systematic theory of value linked with a normative picture of human development. Apart from virtue, the other so-called good things in human life, such as one's own health or prosperity and that of one's family or friends, were "matters of indifference," not goods, though they were naturally "preferable." In a complete process of ethical development, human beings would progress from valuing "preferable" things to recognizing that virtue (conceived as order and rationality) was the only good. Failure to develop an understanding of what was really good produced emotions, such as anger and grief, that were defective and misguided reactions. One of the main objectives of Stoic practical ethics was to cure people of the misconceptions that produced these emotions and to promote the development toward full wisdom that alone brought true peace of mind. Sociability and the desire to benefit others was also seen as a natural instinct in human beings, which should develop toward a sense of kinship with all other human beings as rational animals. The realization of the brotherhood of humankind (which was also seen as the expression of "natural law") was the ultimate ideal and desired objective of Stoic political thinking. Stoics did not favor any specific type of conventional constitution such as democracy or monarchy.

In Stoic physics, the natural universe was seen as unified and coherent. Reality, including god and the human mind, was conceived in wholly material terms. The universe was a total fusion of active and passive principles; the active principle could be understood as fiery air or animate breath (pneuma), and also as immanent god, reason, or fate. The universe was also seen as a seamless web of interconnected causes with no random events. This nexus of events, and the universe as a whole, was understood in teleological terms, as expressing underlying providential purpose or rationality and as being, in that sense, good.

For the Stoics the scope of logic included the philosophy of language and epistemology as well as the systematization of arguments. Chrysippus in particular developed formal logic to a very high level, especially the logic of propositions; Stoics also partly anticipated Gottlob Frege's (1848–1925) distinction between sense and reference. In epistemology, they maintained the empiricist claim that certain kinds of sensory "appearances" form the basis of an infallible grasp of reality. However, they also held that complete knowledge, or wisdom, involves a systematic, theoretically based understanding of reality as a whole.

The goal of philosophical enquiry was an integrated grasp of these three areas. For instance, the Stoic theory of determinism embraces a conception of universal causation (derived from physics), a logical analysis of possibility and necessity, and an ethical account of human responsibility, based on the idea of humans as both rational agents and an integral part of the causal chain. The modern stereotype of the stoical person as one who accepts life's vicissitudes as the work of fate derives from this conceptually powerful set of theories. The seemingly idealized picture of natural human development adopted in Stoic ethics was seen as consistent with the idea, fundamental to Stoic physics, that nature forms an organic and providential whole. The Stoic conception of the good was, in essence, that of structure, order, and rationality, manifested as virtue in the sphere of ethics, as the order of the universe in physics, and as a system of argumentation and knowledge in logic.