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Topic #G57


Stoic physics


15 February 2002
Scribe: Matt Stupar


These minutes were spoken on 25 February; for another version, go to the unspoken minutes



Last Friday’s lecture began with no formal warning as to the immense content that would flow from the lips of the guest lecturer, Stephen Menn.


The Stoics had an elaborate view of physics and considered it to be a part of philosophy.  Since philosophy seeks after wisdom, and physics is part of philosophy, the Stoics believed that the study of physics was an essential step in reaching their ultimate goal of becoming a sage.   Not all people believed that physics was actually a part of philosophy, however.   The Cynics, for example, and Ariston (his view is found at section 160 of page 106 in Hellenistic Philosophy), who was a Stoic himself, disagreed with this conception of wisdom.


The Stoic philosophy could be broken down into three main categories (see section 39 on page 110 of Hellenistic Philosophy):  logic, physics, and ethics.   These three subjects were summed up by an analogy of an egg.  Logic, which is meta-philosophy that deals with our rational discourse, is the shell of the egg and protects the inner contents of physics and ethics.  While ethics deals with the character of an individual and has immediate practical relevance to life, physics deals with nature and has no immediate practical relevance.  It is, however, worthy of being contemplated.  This division is similar to Aristotle’s division between theoretical and practical philosophy.  According to Aristotle, physics, mathematics and theology (or First philosophy) belonged to theoretical philosophy, the end of which is contemplation.  While Aristotle believed that the gods were beyond the realm of physics, the Stoics believed that the gods had physical bodies and should therefore be studied in physics.  They believed that action must involve contact and therefore, the gods would have to have a body in order to influence the physical universe.  This view is summed up in article 28 on page 165 of Hellenistic Philosophy. 



This comparison between Aristotle and the Stoics showed that Stoic theology is physics.  Their philosophy centered on practicality and they tried to do whatever was necessary to live a good life.  Theoretical philosophy was the contemplation of what was most worthy and, in their opinion, aided the practical segments of philosophy, such as reason. 


In response to a question, our guest lecturer explained that the Stoics believed the act of thinking to be the act of a body, but believed that the content of the thought, e.g. ‘that 2+2=4’ was incorporeal. 


The telos formulae (accounts of the goals of human life) were written by all but one of the heads of the Stoic school.  They were, in essence, goals for human life.  These sayings did not oppose each other, but rather built on one another.  These sayings can be found on page 211 of the Hellenistic Philosophy, starting at section six. 


Stoic physics looked very much like biology because they believed that the entire universe was a living organism.  They also believed that there were many gods, but that one main god, Zeus, ruled over all.  This Zeus, who should not be confused with Homer’s Zeus, had absolute reign over the universe.  For the Stoics, everything was considered natural to some degree, and unnatural things occurred with respect to the nature of the individual only. 


Plato’s Timaeus influenced the Stoics greatly.  They did not agree, however, with Plato’s view that matter resists order.  Therefore, they claimed that although everything is in accordance with nature, it is still possible for something to be unnatural in relation to the individual, for example, illness.  The world could still be considered healthy then, even though I am sick.  We can understand this principle in relation to a human being who is considered healthy even though he or she may have a diseased cell.  According to the Stoics, Zeus delegates to each person his or her parts and we, in turn, are expected to help Zeus.  Possidonius was a leader of the Stoic school, who supported this belief by saying that it is the responsibility of a human being to contemplate the universe and to help Zeus to construct it in accordance with nature.  The will of Zeus, however, could override something that was considered important by us, such as health, if he felt that having a virus would be better for us or for the cosmic system or in some other way. 


The professor then made another comparison between the Stoics and the Timaeus.  In the Timaeus, all of the principles in the universe, including the Craftsman, Demiurge, and World Soul are bodies.  Some bodies, such as matter, are passive and some, such as fire or air, are active.  Everything is made up of World Soul and matter.  Plato believed that there was a difference between the Demiurge and the World Soul, but for the Stoics they were the same because they were both bodies.  The Stoics did not consider Zeus to be the creator of soul but to be the soul.  Sometimes Zeus, as fire, consumed the entire universe and sometimes he receded in order to create the universe.  The fire would never completely recede, however, so that order could remain throughout the universe.  Section 61 on page 174 of Hellenistic Philosophy gives a more detailed description of this analogy. 


And then, at certain fated times, the entire cosmos goes up in flames and then is organized again.  And the primary fire is like a kind of seed, containing the rational principles and the cause of all things and events, past, present, and future. -Aristocles, in Eusebius Prep.  Ev.  15.14, 816-817a (SVF 1.98)


This fire was also the seed of rational principles.  This belief arose because the Stoics had to answer the question of where the first thing came from? For example, the first horse.  And the answer was, that it had no father but came from the seed of life, which was Zeus.  Page 133 at section 136 of Hellenistic Philosophy explains the creative process as a type of cosmic embryology:


In the beginning, then, he was by himself and turned all substance into water via air; and just as the seed is contained in the seminal fluid, so this, being the spermatic principle of the cosmos, remains like this in the fluid and makes the matter easy for itself to work with in the generation of subsequent things (Diogenes Laertius, 7.136, IG II-20).


Much the same as we see the plan for human life encoded in DNA, the Stoics saw the plan for life in the creative fire.


The Stoics borrowed this general notion from the Timaeus but did not feel that Plato’s explanation could work since they could not reason how an incorporeal god could act on the physical world.  Therefore, their plan was more practical and easier to explain than Plato’s more theoretical approach. Stoicsw believe that Zeus, who embodies all virtues, applied his knowledge of physics to create the world, and in this way made it the best according to nature.  Humans, therefore, can know the general physical principles, subject to our limited knowledge of the cosmos. 


The universe is so well ordered by Zeus that even an evil person unwillingly follows Zeus’ plan.  A good person, on the other hand, is good because he or she chooses to follow his plan.  This strength of Zeus’s will is described in a short hymn of Cleanthes found at section 22 on page 141 of Hellenistic Philosophy.  Although gods also have bodies, only humans are capable of doing evil, since gods were never babies and therefore, never had to learn virtue.  Although evil is contrary to Zeus’s plan, it can never destroy his plan because it only imparts unnaturalness to the individual and not to the world as a whole. Zeus never actually has to intervene in human affairs.  He might intervene if the world reached an ultimate low, but it would never reach that low because he is constantly governing it.