If men are to be motivated to fight with commitment, they need to be given good reasons for doing so. In Homer, it is a mark of aristocratic status that one is able to persuade others to risk their lives. Yet Homer also highlights the importance of discussion between leaders who meet in common council at the end of the day. The views of one speaker need to be tempered by those of his listeners so that there is a reasoned consensus. By the sixth century, however, speakers found themselves faced by the much more demanding audiences of the citizen assemblies, raucous, volatile and much less ready to defer to aristocratic status. New demands on speakers forced the Greeks to think about the nature of rhetorike, rhetoric, itself, and how to exploit it effectively before audiences. Was it even to be seen as a skill that could be taught? Yes, said the rhetorician Gorgias, who arrived in Athens in 427 from his native city, Leontini, in Sicily. Gorgias had learned his skills negotiating property disputes and had come to Athens to plead for the city to support Leontini against its neighbour Syracuse. He was unashamedly a performer— he would stride into the Athenian theatre, call out “Give me a theme” and then declaim on it without hesitation—but he gave younger citizens starting their political careers in the assembly the confidence that the art of good speaking could be learned.1
Yet Gorgias’ success highlighted the tension which lay at the core of rhetoric. The effectiveness of a speech seemed to depend as much on the emotional power of the speaker, his learned skills and oratorical devices, as on the quality, in rational terms, of its argument. In the activities of the Athenian assembly, for example, during the tense days of the Peloponnesian War between Athens and Sparta (431–404 B.C.), the citizens, swayed by powerful speeches, decided one day in 427 that all the men of the island of Mytilene, captured after a revolt, should be executed. When tempers had cooled the next day, they realized that so harsh a decision might rebound against them and they reversed it.2 (A trireme sent off hurriedly to communicate the reversed decision arrived in Mytilene just as the executions were beginning.) In 406, the assembly was persuaded by impassioned speakers to order the execution of eight of its generals who were accused of failing to pick up shipwrecked sailors after a battle. After the executions, the assembly regretted its decision and somewhat hypocritically condemned the speakers for “forcing” it to act the way it did. So emotions could be seen to overrule reason. Playwrights and philosophers explored the dangers of rhetoric. Parmenides has the goddess who declaims his ideas tell her listener: “Now I put an end to persuasive logos and thought about truth, and from this point do you learn mortal opinions by listening to the deceptive appearance of my words”—words that, when separated from the logos of argument, the goddess recognizes, might prove in themselves “deceptive.”3 In his play Clouds, Aristophanes sets up a debate between “Just Speech” and “Unjust Speech,” in which “Unjust Speech” triumphs through the unscrupulous use of verbal trickery.
These concerns were countered by teachers of rhetoric such as the influential Athenian Isocrates (436–338 B.C.), who looked back to a golden age when, he claimed, the great men of Athens—Solon, Cleisthenes the bringer of equality among citizens, Themistocles the hero of the Persian Wars, and Pericles—had used rhetoric solely for the good of the state. The very success of Athens in earlier times had shown that good speaking could offer a pathway to greatness. What was vital, argued Isocrates, was the moral independence and integrity of the speaker, and training in moral responsibility was an essential part of training in rhetoric. “The stronger a person desires to persuade hearers, the more he will work to be honourable and good and to have a good reputation among the citizens.” 4 Isocrates even recognized that at times a “moral” speaker might have to put the needs of the Greek world as a whole before the concerns of his native city. This stress upon the moral qualities of the orator was to be echoed by the Romans, by the orator and statesman Cicero and by Quintilian (c. A.D. 96), in whose Institutio Oratoria an upright character and high ideals are presented as the fundamental qualities of a good speaker.
An input of emotion in a speech was not necessarily a bad thing. In his Rhetoric, Aristotle listed the components of a good speech, using the word logos to describe the speech itself: “There are three kinds of persuasive means furnished by the logos: those in the character of the speaker, those in how the hearer is disposed, and those in the logos itself, through its demonstrating or seeming to demonstrate.” 5 One could not, argues Aristotle, disassociate “the character of the speaker” from the rational elements (its “demonstrations”) of the speech itself. They are both essential components of a speech, and the emphasis should not be on trying to eliminate emotion but to make morally responsible use of it.
Yet for one Athenian, Plato (c. 429–347 B.C.), this was not enough. Plato lived through a time of change and disorder. His native Athens was defeated in the Peloponnesian War by Sparta (404 B.C.), its great walls demolished and its empire dismantled. A new “Government of Thirty,” to which Plato had some family links, degenerated into tyranny, and after the restoration of Athenian democracy a witch hunt was launched against Plato’s mentor, the philosopher Socrates. Socrates had made himself a well-known figure in Athens, not least through his practice of challenging every assumption of anyone he questioned. “The unexamined life is not worth living,” he insisted; “the most knowledgeable man is he who knows he knows nothing.” His demolition of any conventional belief held without reflection proved intensely irritating, especially at a time of defeat and political turmoil for Athens. Eventually the patience of his fellow citizens was exhausted, and in 399 they put Socrates on trial. “Socrates does wrong,” the charge read, “by not acknowledging the gods the city acknowledges and introducing other, new, powers. He also does wrong by corrupting the young.” Such vague charges were a familiar part of Athenian political life and could usually be met by counter-accusations against one’s opponents. Socrates refused to debase himself and argued instead, and provocatively, that he should be honoured by the city for his work, not denounced. This only outraged his accusers further, and he was found guilty and, in a rare case of Athenian political intolerance against a fellow citizen, sentenced to death.6
The lesson Plato drew from Socrates’ condemnation was that the emotional and ephemeral impulses of the masses could lead to the commission of evil, in this case, the execution of a “good” man. “Good” and “evil,” it appeared, were unstable concepts, relative to the moment. In his work Gorgias, Plato uses the example of Gorgias himself to pour scorn on the idea that a speaker can bring truth to his listeners—whether he himself recognizes it or not, his art lies primarily in deception. For him, Isocrates’ claim that it was simply a matter of training speakers to be more morally upright failed to reach the heart of the problem; instead what was needed were objective standards by which to judge moral concepts such as “good,” “evil” and “justice.” Establishing these standards was the task that Plato set himself.7
One of the major influences on Plato was Pythagoras. Pythagoras, active at the end of the sixth century B.C., had been dead for a hundred years, but his followers in southern Italy had preserved his teachings, and Plato visited them in 388 B.C. Among these teachings was a belief that numbers underpinned the natural world. Pythagoras had used the example of a string stretched across a sounding box. Pluck it and record the note. Halve the length of the string and pluck it again, the note is precisely one octave higher. So unseen numbers appear to be present at a different and, Plato argued, more significant level than the world appreciated by the senses. Plato developed this idea to suggest that not only numbers but values and even objects existed beyond this world and at a more perfect level of reality. So while a picture may be beautiful, its beauty, which is essentially transient, is only a reflection and a part of a much greater eternal beauty. This Form of Beauty, as Plato called it, comprised all the elements of beauty known on earth but was in itself greater than they were. It was far more valuable to come to know this Form of Beauty than to search without success for transient beauty in the natural world. There could be Forms of many different entities—in his so-called Seventh Letter Plato suggests there might be Forms “of shapes and surfaces, of the good, the beautiful and the just, of all bodies natural and artificial, of fire and water and the like, of every animal, of every quality of character, of all actions and passivities.” 8 Furthermore, Plato suggested that the Forms were not all equal, existing alongside each other, but that they could be arranged hierarchically. If the Forms of “Justice” and “Beauty” are “good” in themselves, then they must form part of a superior Form of “the Good,” which could be compared to a sun among other lesser sources of light.
The world of Forms could be grasped by the human soul, which Plato believed was immortal and passed from one body to another on death. Plato was fascinated and perplexed, as many Greek philosophers were, by the relationship between reason and emotion. His solution was to see the soul as split into three parts: a reasoning part, another sensual part based on “desire” (hunger, thirst, sex) and a third on “spirit,” which encapsulated emotions such as anger and the desire for honour and reputation. To Plato the reasoning part was by the far the most important; he argued that maturity, in effect the ability to act virtuously, came from bringing the “desiring” and “spirited” parts of the soul under the control of reason.9 The reasoning part of the soul could achieve its own maturity by grasping the nature of the Forms, which, Plato claimed, it had actually always known but had forgotten. He makes the point in his dialogue the Meno. Meno is a slave who is led through a mathematical proof that deals with the area of a square (which quadruples when the length of its side is doubled). Plato argues that the knowledge that the proof was true was concealed in Meno’s soul and simply had to be “recollected.” The proof relating to the area of a square could be said to exist as a truth which would be true in any circumstances at any time. In other words, it exists independently of the material world and continues to exist even if no human soul is aware of it.
A mathematical proof such as that presented to Meno can be proved by and to any whose minds are capable of elementary deductive logic. But Plato goes on to argue that concepts such as justice, beauty and good are similar to mathematical proofs in that they also exist as eternal truths (“Forms”), independent of the material world. He readily acknowledged the difficulty in grasping these Forms. Few had the intellectual and reasoning power required to conquer their “desire” and “spirit” and set out on the arduous intellectual journey required. In the Phaedo Plato talks condescendingly of “the lovers of spectacles and lovers of sounds, who delight in fine voices and colours and shapes, and everything that art fashions from that sort of thing . . . but their minds are incapable of seeing and delighting in the nature of the Beautiful itself . . .” In other words, the reasoning part of their souls is incapable of asserting its power over the other parts. Those who had the intellectual ability to understand the Forms should be selected when children and trained over many years in the use of reason. They (and Plato was unusual for his times in including women as well as men) would gradually come to develop an understanding of the Forms, until finally, after many years of intense reflection, their true and eternal nature would be revealed.
Yet when they had grasped the Forms and the eternal truths enshrined in them, the task of the intellectual elite, “the Guardians,” as Plato termed them, was just beginning. It was they who would take on the task of running society according to their knowledge of the nature of justice, good and similar concepts. They were, as Plato put it, like doctors who knew what was best for their patients and were thus justified in overruling the patients’ own beliefs about their illnesses. If anyone resisted them, the Guardians were justified in exiling or even, according to Plato’s late work the Laws, executing them.
The search for an understanding of the Forms, as well as the implementation of them, required absolute dedication, and those selected to undertake it must not let themselves be diverted by emotion or rhetoric. Plato’s world was one in which there was little place for spectacle, theatre or the arts (a beautiful object could only be a pale imitation of the Form of Beauty), spontaneity or sexual passion. The Laws, in particular, written when his idealism appears to have soured, seems to demand a joyless society. However, for Plato the achievement of knowledge of the Forms was such a satisfying task in itself that it would transcend any knowledge of the world apparent to the senses. He went further; knowledge gained of the Forms was so significant that observations of the actual world should be disregarded if they were in conflict with the reality of the Forms. “We shall approach astronomy, as we do geometry, by way of problems, and ignore what’s in the sky [my italics], if we intend to get a real grasp of astronomy,” as he puts in The Republic, his most famous work, on the nature of good government. 10
This amounted to a direct attack on the mainstream scientific tradition of Greek thought, which relied, as we have seen, on empirical observation. While Plato stressed that the Forms could be grasped only through reason, was it in fact possible to use reason to prove that the Forms, indeed a whole world of unchanging immaterial “objects” beyond this one, actually existed? Even if it were, how was it possible to be sure that anyone had grasped the Form of, say, “the Good” correctly, and how were disputes to be resolved if there were rival interpretations? In practice, Plato’s assertion that such conflict was impossible because all those who grasped a Form would agree on its nature seems untenable. The fundamental, and perhaps fatal, weakness of Plato’s philosophy lies in the difficulties of finding axiomatic foundations from which the nature of a Form of, for example, Beauty can be deduced. Without axioms proper reasoning was impossible, and in terms of practical politics it needed only a powerful individual, institution or government to claim that it had discovered the Platonic Forms, and with them the right to impose them on others, for a dictatorship to emerge. Among its casualties would be the speculative tradition of empirical research, to which Plato appeared to give such little value.11
Platonic thought assumes that the material world is not the ideal setting for the soul. A more satisfying home exists elsewhere, in the immaterial world of the Forms. This was a revolutionary concept in the Greek world, where, for example, the afterlife was traditionally seen as a shadowy and unfulfilling existence, and it created a radical disagreement between those who attempted to live life to the full within the material world, and whose philosophies and ethical systems reflected that, and those who saw the soul as trapped temporarily in this inadequate and transient world before a greater one to come. Platonists also assumed there was a deep gulf between the world of the senses and that of the Forms. Because it was accessible to so few and needed such an arduous training to reach it, the world of the Forms was divine in a very different sense from that of the traditional world of the Greek gods, whose human forms, behaviour and rich mythology of exploits made them comprehensible, even accessible, to all. If a Form, say that of a supreme Good, was equated with an actual God, then he would indeed be an awesome and remote one. Inherent in Plato’s thought was a massive realignment of the relationship between human beings and “the divine” that involved, inevitably, the diminution of the place of “the ordinary man” in the scheme of things. The fruits of Platonic reason might not be self-confidence but the opposite—a realization of how insignificant human beings were in the face of the superior, unchanging, hierarchical world of the Forms. Explicit too was the grading of human beings into a minority who could grasp the nature of the immaterial world and the mass who could not and were therefore dependent on the minority for elucidation. Effective reasoning was the preserve of the few, who had to persuade or coerce those who were unable to grasp the nature of the Forms.
Plato’s insistence on an other-worldly basis for ethical belief can be contrasted with Aristotle’s. In many respects Aristotle’s thought is as alien to us as Plato’s: he was aristocratic by temperament and supported the subjection of women and the institution of slavery. Only the free mature male, according to Aristotle, is able to think rationally. Yet, unlike Plato, Aristotle was concerned to create an ethical system that was based in the everyday world of human existence. He was much more sensitive to and accepting of the humanity of others than Plato was. “One may observe in one’s travels in distant countries,” he writes in the Nicomachean Ethics, “the feelings of recognition and affiliation that link every human being to every other human being.”12 Virtue (the word used was arete, often translated as “excellence,” although this risks depriving it of its ethical connotations) is not an abstract principle to be searched for outside the material world. It exists when a human being lives a life in which his nature as a human being is realized at the highest level. By living in this way he will reach eudaimonia, a state of well-being or flourishing. This state does not just happen; it has to be worked for through the actual experience of living. First a child must be brought up by its parents to be disposed towards the doing of “good,” but he can only become “good” through the active doing of “good” acts. First the right orientation, the desire to do good as a way of living, then the practical experience of doing “good,” which somehow fixes “goodness” within the character of the doer. (This concept, important for educationalists among others, has gained new life in modern philosophical debates.) Yet what does it mean to act in a “good” way? In everyday life the individual is faced with a host of situations. Suppose one takes one type of “good” action, for example, behaving courageously. But while courageous behaviour is undoubtedly virtuous, in practice some undoubted acts of courage, for instance, attacking an armed soldier while unarmed, are scarcely rational. The individual has to exercise discrimination based on knowledge of similar situations and on a thinking-through of possible outcomes to distinguish which courageous acts are likely to have some “good” effect. Ethical judgments should not be based on the emotions of the moment—reasoned control of emotions is central to Aristotelian ethics—and so with increasing experience each individual is likely to develop his or her own moral code, general principles by which they act. However, the ability to adapt this code to the demands of a specific situation must never be lost (it would be a degradation of the power of reason if it were). In Aristotelian ethics there are no absolutes that can be used to allow the individual to surrender his duty to accept responsibility for his own actions in a variety of different circumstances. Aristotle goes further, suggesting that the courageous or other “good” act becomes a truly virtuous one only if it is carried out for its own sake, not just as a means to another end.
A person who combines the right disposition with the ability to be able to discriminate in actual situations will, Aristotle argued, eventually achieve a life in which he is at peace with himself. Everything will come together in harmony, eudaimonia, a complex state in which success in human affairs, moral goodness and the ability to use rational thought at its highest level seem to co-exist. (It is perhaps too simplistic to group these attributes together. While Aristotle believed that a state of contemplation, which often requires isolation, was the highest state of man, he was also acutely aware that human beings need company if they are to be fully “themselves.”)
Every individual has the potential to find his own eudaimonia, the natural end of being a fully functioning human. Aristotle is typical of Greek thinkers in having a confident and optimistic view of human nature. He proclaims that it is worthwhile being human, and, unlike Plato and later Christian thinkers, he says little about the possibility of natural desires pulling one away from eudaimonia towards some lower state of existence. “Nature always produces the best,” he says on several occasions; in the Nicomachean Ethics he states that “all the virtues of character seem to belong to us from birth . . . For we are just and moderate and courageous and the rest straight from our birth . . . even children and animals have these natural dispositions, though they evidently prove harmful without rational guidance.”13 In short, becoming virtuous involves using one’s power of reasoning to shape virtues that are innate. Aristotle assumes that human beings will want to achieve the pleasure of reaching their full and undoubted potential. As an inherent condition of being human, that is the direction in which they are oriented.
In Raphael’s famous Vatican fresco the School of Athens, Aristotle and Plato are shown among the assembled philosophers. Plato’s hand points upwards to the heavens, Aristotle’s down towards the earth. They represent not only themselves but two contrasting approaches in the quest for certainty. For Aristotle certainty has to be found in this world through the painstaking accumulation of empirical evidence and reasoned deduction from it. It is always subject to reason and challenge through the acquisition of new evidence accumulated by the senses. Outside the world of abstract mathematics and logical syllogisms, knowledge is always provisional. Plato, by contrast, rejects the world of the senses altogether. It holds no real value in comparison to the immaterial world of the Forms, where truth alone resides. The way that these two approaches to certainty were developed in the next centuries and woven into the fabric of Christianity will form a major theme of this book.14
Meanwhile, the world of the fourth century B.C. in which both great thinkers taught was in the process of being transformed. The political developments of the next 700 years and the survival of the Greek intellectual tradition are the subject of the next section of this book. In both religion and philosophy, in all its branches, including science and mathematics, there were still important achievements to come.