Debating schools

Not so thorough histories of philosophy tend to view Plato and Aristotle as an end of a progression starting from Socrates and even pre-Socratics. Yet, both philosophers did found schools of their own, which were active long after Plato and Aristotle had died. We've already seen that the followers of Plato emphasized the role of numbers even more than Plato had, either discarding the Platonic ideas or identifying them with the numbers – they clearly loved mathematics.

Followers of Aristotle took the opposite route and followed their master in concluding that numbers cannot be the primary explanation of all things: after all, how could unchanging numbers explain world of change around us. Instead, followers of Aristotle, such as Theophrastus, thought that their teacher's notion of a desire for ultimate perfection as the primary cause of all change and movement was at least more promising first principle. That doesn't meant that e.g. Theophrastus would have accepted his teacher's philosophy wholesale. Indeed, Theophrastus might not have accepted even the Aristotelian perfect being as the prime mover: why would an urge to perfection cause many different kinds of movement? Instead, Theophrastus suggests that perhaps e.g. stars do not move, because of an urge to perfect themselves, but because it is in their nature to move in a certain manner.

Despite their differences, Aristotle and Theophrastus shared some clear methodological elements. The most important is their acceptance of reliable experience as a source for testing metaphysical theories. It is then no wonder that Theophrastus spent quite a large part of his life in empirical studies of e.g. plants. But it is not Theophrastus and his even lesser known followers philosophers think of, when they are considering the time after Plato and Aristotle. Instead, it is Epicureanism and Stoicism that come to mind as the epitomes of philosophy in the so-called Hellenistic period of history.

Of these two schools, the Epicureanism was more faithful to its founder Epicurus, and indeed, some of its followers boasted that they still held the original ideas of Epicurus; their critics retorted that initiation in the Epicurean wisdom was like castration in its irreversibility. Stoics, on the other hand, were not so attached to the doctrines of the founder, Zeno, and even if they did not straightforwardly contradict him, they surely attempted to develop his views and emphasized different parts of philosophy according to their own interests.

Just like we saw in Aristotle, philosophy was not seen anymore as an undivided unity, but as consisting of interconnected modules that could be studied independently of one another, although there was a clear hierarchy of more and less important modules. Both Epicureans and Stoics were interested of the question of determining the basic modules and organizing them into a systematic whole. In Stoic school especially, number of schemes were suggested, but soon both school appear to have settled to a the three-part division of philosophy, where different parts answered different basic questions. The first question of the proper way to reveal truth was studied by Epicurean canonic and Stoic logic, while the second question of the structure of the world was studied in both schools by physics, and finally ethics investigated how one should live one's life.

Following Aristotle, both Hellenistic schools conceded that search for knowledge must begin from sensations or perceptions. In fact, they perhaps went a bit further and stated that perceptions were the necessary basis of knowledge, while Aristotle has emphasized the human capacity to recognize basic truths common to all experiences. Epicureans went even so far as to declare all information given to us by senses as true: if we see red, then we definitely see red. It is only when we start to interpret our sensations that mistakes start to happen, for instance, when I assume that there is a real red object causing the red sensation, if it just a hallucination. Still, even in these cases the mistake can be revealed only by other sensations, for instance, by our touch showing that there's nothing but air in front of us.

On the other hand, Stoics emphasized that not all perceptions are trustworthy as such: if I hallucinate, I have the misleading tendency to believe that what I hallucinate is really there. Thus, only some perceptions are to be accepted as reliable indicators of something that truly exists, and it is only such reliable perceptions we can accept as the foundation of truth.

For Epicureans, sensations were enough for knowledge. True, some reasoning might be in order to reveal things that we cannot directly experience, but even here one must be careful and admit the limits of human mind. Thus, they felt no need to carefully determine the intricacies of reasoning: why bother, when it is always better to directly perceive than to reason things.

For Stoics, on the contrary, the perceptions were only the basis of the truth and they had to still be transformed into the form of rational thought, that is, they had to be given a linguistic shape. In this part of their logic Stoics clearly shared common ground with Aristotle and his methodology: Stoics begin by defining how words are produced, how they are combined in e.g. statements and how statements can be deduced from one another. The main difference between Stoic and Aristotelian logic is that Stoics were far more interested of deductions based on the form of the whole statement: for instance, Stoics noted that a statement of the form ”if A, then B” could be used to deduce statement B from statement A.

In addition to a methods of finding or ascertaining truths, Stoic logic also contained practice for disseminating truths in form of speeches and writings. Epicureans were here also willing to ignore the subtleties and recommend only the use of every-day parlance so that truth would not be hidden behind lofty words.

Both Epicureans and Stoics were in a sense materialistic compared to Platonic and Aristotelian philosophies. This was especially true of Epicureans who had borrowed their worldview from atomists. The Epicurean world consisted mostly of material things, and these things required a container or empty space for movement. As Epicureans could not conceive how bodies might exist and be infinitely divisible, they supposed all division must end at a final point of hard and unbreakable atoms, of which all the other bodies were then composed. Furthermore, they could not conceive any limits for the world, and because in an infinite world, a finite number of atoms would quickly disperse and form no complex bodies, they also supposed an infinity of atoms.

This was as far as Epicureans were willing to let reason guide them. Beyond that, they assumed that the atoms must have somehow coalesced into such wholes as the cosmos we see around us – in fact, there probably were infinity of such wholes in existence. Yet, of the further happenings of such a cosmos, nothing certain could be said – perhaps lightning was caused by these reasons, perhaps by others.

Like in their logic, Stoics leaned in physics also to similar considerations as Aristotle, that is, they assumed that everything in the world consisted ultimately of a featureless material substance, sort of primordial slime. To make this substance into concrete things, an active force was required, on the one hand, to divide the original substance into pieces, on the other hand, to give different characteristics to different parts of the substance.

The Stoic active force was then nothing inseparable from the material substance, but was necessarily incorporated within matter. Some Stoics identified it with a particular thing, such as Sun, others thought only the whole cosmos could suffice as the body of this activity. Needless to say, this materialized force organizing everything played the role of God: it had created the cosmos as we knew it, and one day, when the current world was destroyed by fire, it would build everything anew.

The difference between Epicurean and Stoic notion of the origin of cosmos led to a completely different manners of looking at the world. While Epicureans admitted the impossibility of certainty on individual physical questions, they were eager to note that at least we did not need to assume any divine origin for phenomena: lightning was probably not caused by the wrath of Zeus. Epicureans did not deny the existence of divinities, although they insisted that gods must also be material. Still, they assumed that such perfect beings must be completely uninterested of anything beyond their own never-ending pleasure and thus could not be the cause of physical events. In this manner Epicureans wished to show how irrational it is to fear thunder and other physical events or try to appease gods.

Stoics were, understandably, of the opposite opinion. True, their original divinity was not supernatural either, but it was apparently very interested of the world around it. The cosmos had a purpose and it must show traces of divine influence all around. Stoics went even so far that they accepted traditional forms of divination as more or less reliable methods of ascertaining divine will.

The doctrines of the Epicureans and Stoics concerning the world as a whole reflected also their view of the human beings. Epicureans supposed that human beings must consist of atoms and that within the hard shell of human body existed a finer collection of atoms capable of sensing emanations from other atoms. Without this indwelling finer body, the external body would be just a lifeless heap, but furthermore, without its shell, the finer body would quickly scatter in the wind. No part of human beings could then exist without the body, but Epicureans saw no reason for sadness in this fact. Indeed, they even applauded the thought that human beings had no reason to fear eternal torture after death.

Stoics also shared the idea of two parts within human beings, but with them this view was better justified by their general doctrines. Just like world was passive matter controlled by an active force, all particular beings had a part of both the universal matter and the universal force. In case of humans, this embodied force could be called soul. Stoics were not really sure what happened to this force after the death of human beings. Perhaps it continued its individual existence for some time, if it just found some embodiment beyond its original body, but at least when the whole world was destroyed, the individual souls would return to the original life force and be swallowed in it.

But is is not logic or physics we remember when we speak of Hellenistic philosophy, but ethics. Indeed, both Epicureans and Stoics thought that the aim of philosophy was to show how we should live. As with their physical doctrines, in ethics both schools were influenced by previous philosophers, but they also developed the ideas of their predecessors considerably.

Epicureans were often disparaged as followers of Cyrenaic school, but they were quick to distinguish their views from the views of their hedonistic predecessors. True, Epicureans also admitted that pleasure was the end of good human life, but their pleasure resembled more what Aristotle had called happiness. Epicureans assumed that not all pleasures were of equal rank, because some of them involved pain and uneasiness, just like drinking too much wine results in a headache

Indeed, Epicureans thought it best to search for stable pleasures, like aesthetic enjoyment of art and delight on the presence of good friends, and pleasure that were necessary for human life, such as eating nourishing food when truly hungry. Especially they strived for painless life, and this quest for removing pain required also intellectual capacities. Because bad luck could strike anyone, a capacity to accept and endure even unpleasant states was also required. A truly happy man would then not just live the most pleasant life as possible in the circumstances, but he must also be wise and virtuous.

Stoics were said to have been influenced by Cynics, and indeed, Zeno was apparently thought by a Cynic. Thus, they shared something of the austere way of life favoured by Cynic and especially endorsed the ideal of living according to nature. But unlike Cynics, Stoics had a developed theory of the world and its denizens, and in this case, of the living beings. The aim of every living thing, according to Stoics, is to maintain itself, and therefore even plants feed themselves. While plants are senseless, animals can sense and feel things and therefore they can even feel when they have stumbled on something useful for their own maintenance: in that case they feel pleasure. Humans, on the other hand, have developed even further and have rational abilities to analyse their situation. Thus, they need not pleasure to know what to do, and instead, they should live by the guidance of their reason.

Now, reason and life according to it are then the only truly good thing, without which life would be full of misery. Compared to rationality, all else is useless: you might have fancy clothes or not, and it would not affect the quality of your life. Needless to says, Stoic were quite skeptical of emotions, which were more like a remnant of animal life. Especially negative emotions are to be avoided, and an ideally wise person would at most enjoy life, be cautious of dangers and wish for a good future.

This figure of an ideally acting person or wise sage was then important for both Epicureans and Stoics, and while one emphasized pleasures and other life according to reason, they both accepted that a life of a wise person would be both pleasant and rational. Stoics especially emphasized how different sages were from ordinary people. Radically they insisted that all people who were not sages would live badly, that is, there was no mediate stages between complete wisdom and utter depravity. Then again, becoming a sage was apparently an incontrovertible revolution, and once you knew how to live properly, you couldn't turn back.

Even though both Epicureans and Stoics spoke of ideals of wise persons, their ideals were also different in important points. Epicurean wise man was still in a sense an egoist, because it was only the pleasure of his own and his close friends that interested him mostly. Epicureans were doubtful of all communal efforts beyond association of friends, and they even felt family life to be a hindrance. Still, they suggested that even a wise person should follow the customs of his living environment, just as long as they were not completely against good reason.

The ideas of Stoics provide an interesting contrast to Epicurean views, because while latter accepted social norms, at least early representatives of the Stoic school were apparently still closer to the Cynic teachers, as they insisted that a wise person could ignore common customs, if it was rational to do so: if a sage wanted to cannibalize his companions, then it was good to do so. Later Stoics were, on the contrary, eager to point out that even sages lived usually customary life – they just did it better than others. On the other hand, communal life was far more important for Stoics than it was for Epicureans. Early Stoics spoke even of founding a community of wise people, which apparently resembled in some measure Plato's ideal community, because, for instance, instead of individual marriages, all wise shared their spouses with one another. Even later Stoics admitted that the life of a sage contained working, parenting children and taking part in communal endeavours – no wonder then that Stoicism was more accepted in the state-oriented Roman empire.