The philosophy of the Stoics played a central role in developing the ideals of the Roman ruling classes. This philosophy emerged in Greece in the early 3rd century B.C. with the thought of Zeno, a native of Citium on the island of Cyprus. He and his followers, such as Cleanthes, took their name from the colonnade, or covered porch, in the agora (marketplace) in Athens. These philosophers and their followers were given to strolling in this colonnade, or “stoa,” discussing ideas; hence, they took the name “Stoics.” Zeno himself was interested in metaphysics—speculation about the ultimate nature of reality—and logic: his ethical thought developed as a corollary of this interest. He spurred a tradition that would eventually pass westward to Rome in the Hellenistic age. Roman thinkers deepened and refocused the Stoic tradition: they were interested less in metaphysics than in ethics: living one’s life in harmony with the good.
Stoic ethical thought is grounded in reflection upon the nature of the universe, which depends upon a particular view of divinity. Hence, in many ways, Stoicism can be seen as a form of personal religion as much as it can be understood as a philosophy. The Roman thinkers, following their Greek predecessors, referred to the divine in a number of dimensions: Nature = Reason = Spirit = Divine Logos = God. All of these are ways of talking about ultimate reality, if a particular Stoic went through the entire equation I offer above; most, but not all did. This notion of “God” should not be confused with monotheism of the Judeo-Christian-Islamic tradition. The Stoic concept is often better seen as a spiritual interpretation of the material universe. The Logos is seen as a supra-rational reality that is infused throughout the cosmos. The discussion of these dimensions below is offered to show how they cohere, and at times, diverge. Some Roman Stoics were materialists while others saw a supernatural truth behind the suffering of the world. Among educated Romans, the ethic of Stoicism was enormously influential since it fit well (or was made to) with conceptions of noble virtue inherited from early Republican times.
1) Nature = Reason: We moderns tend to think of “nature” as flowers and trees, etc., as opposed to the artificial world of humanity. But “nature” (Latin natura) for the ancient philosophers refers to the idea of “reality” itself: “that which exists.” While Latin has a way of speaking about “things”—res—the term natura constitutes the sum of all “things as they are” in philosophical discourse. This is important. The Stoics conceived of “nature,” or reality, as a rational order. The natural world obeys regulative principles—in other words, the universe behaves in reasonable ways—and human beings, as a part of nature, should seek to conform to the principles of nature. In short, we should seek to conform our minds to reality and to obey the dictates of our natural reason. Reason is part of human nature (or human reality); hence, human nature and the natural world conform to one another (or should). Our minds—through reason—are well-fitted with the cosmos: the universe is intelligible (though some Stoics would differ on whether it is intelligent). We need only to grasp and live by this congruity between mind and world to live a happy (or wise) and fulfilling life.
2) The Divine: “Nature” and “Reason” are synonymous with “God” for the Stoics who saw intelligence in the Cosmos. Both reason and nature are emanations of the Divine Logos, or Divine Reason (“logos” is Greek for “reason,” “logic,” “word”). Human beings possess a spark of the Divine Logos—our human reason, our participation in reality—and we should seek, they argue, to follow its dictates in all things. Hence, our human reason is our connection with the divinity of nature, or the real. Here, we should be careful: some Stoics would develop a concept of God that looks very much...