It's been said that everything in western cultural history is Socrates and footnotes. It's hard to believe that an unemployed stonecutter could influence billions of people, but it's true.
We pick up the story with ancient Athens. For 50 years, this city-state had been the greatest power in Greece. Then came the Peloponnesian War (431-404 B.C.), their 27-year-long conflict with Sparta, the great city-state to the south. Athens knew they would lose this war for ten years, but they kept fighting. The end was a bitter, humiliating defeat by their mortal enemies. And you thought you had a bad year.
The Athenians could see the light at the end of the tunnel, until it ran over them. So could the philosophers, who tried to make the best of a very bad situation. As Athens crept closer and closer to disaster, many of her people began to abandon their traditional gods, and to turn to the philosophers for truth and guidance. The Sophists were ready.
The original wise guys
Sophists were the originators of that great tradition now carried forward by late-night infomercials, the first pop psychologists, the original success gurus. They were the "learned ones" who could teach you how to succeed in hard times. They wrote how-to handbooks on nearly every subject, and traveled around the country conducting seminars and collecting large fees.
In time the most popular of the Sophists became international figures, in demand all over the Mediterranean world. They would advise famous marriages, educate wealthy children, and guide kings and princes. Their services were available to the highest bidder. We have Personal Digital Assistants, tiny computerized calendars in our hands; they were Personal Philosophical Assistants, the best the world had to offer before Bill Gates.
Over a single generation these Sophists became the great celebrities of their culture. They were the first to argue for subjective ethics, the idea that no absolutes exist (itself an absolute statement, when you think about--or even if you don't). According to their philosophy of life, the only wrong idea is the idea that an idea can be wrong. I'm not sure what that means, but neither were they.
In time the Sophists settled on the practice of rhetoric--the art of persuasion by eloquent speech. If no absolute values can be relied upon, the best we can do in life is convince others that our own subjective ideas are right. The Sophist teachers became brilliant debaters, learning to persuade gigantic crowds of the truth of their chosen ideas. The rest of the intellectual world hated them, for they could never win an argument with them. No matter how wrong their positions seemed to be, they could persuade the crowds that they were right. They were the first Teflon philosophers.
Talk show ethics got their start with the Sophists of ancient Greece. What you believed wasn't nearly as important as convincing others that you were right, or at least entertaining. To their credit, the Sophist argument for natural rights (everyone is right, because no one can be wrong) made them oppose the slavery which was common in the day. Other than that contribution, the best thing we can say for the Sophists is that they made better philosophers better still. No Sophists, probably no Socrates.
We might add that the Sophists never really went away. Postmodern relativism, the idea that there's no such thing as objective truth (itself an objective truth claim) can be traced all the way back to the Sophists. I'm not grateful.
From stonecutter to soul shaper
Philosophers come in all shapes, sizes, and motivations. In the case of Socrates (470-399 B.C.), his was the oddest of all three. He was a squat, little man, quite ugly, described as having "strangely staring eyes." He was the son of the stonecutter Sophroniscus and his midwife Phainarete. By trade he was a stonecutter himself, but he did not follow his profession. This single fact led to much verbal abuse (and sometimes worse) from his wife Xanthippe. No wonder he wanted to get out of the house and down to the philosopher's hall every chance he got.
Plato, Socrates' most famous student, spoke often of the man's amazing physical toughness. Plato claims proudly that his teacher could drink any man under the table "when necessary." (He doesn't say when that is.) Socrates possessed great moral courage, refusing to compromise his beliefs even in the face of impending death.
He was a man of enormous intellectual concentration. For instance, while serving in the Athenian army stationed at the town of Potidaea, Socrates is said to have stood still for a day and a night, thinking out an intellectual dilemma. Indifferent to his surroundings or bodily needs, he stood and thought while the armies fought all around him. Apparently the other side didn't consider him much of a military threat. Nor did he.
Xenophon, one of his greatest admirers, shows why:
Socrates was so pious that he undertook nothing without the will of the gods; so just that he did not one injustice--more than that, he was kind to everyone who came in contact with him. He was so much the master of himself that he never preferred what was merely pleasurable to what was good; and so virtuous that he never made a mistake in the choice between the good, the better and the worse--in a word, he was the best and happiest of all mankind.
How did such a strange person become so influential? Through two words.
Do you know yourself?
The oracle at Delphi was the greatest tourist attraction in ancient Greece. Conventional wisdom said that the gods spoke to mortals here. The "oracle" was actually a female, sitting on a chair suspended over a shaft which led down into the earth. A worshipper would approach and ask his question of the gods. Mists would rise from this shaft, and the woman would speak the word of the gods to the person. Answers were usually cryptic and ambiguous at best--like the horoscope in this morning's newspaper.
Socrates made his pilgrimage to this oracle, as did thousands of others in his day. The oracle told him that he was the wisest of all men, for while no one knows anything, he knew that he knew nothing. Then the oracle gave him this motto for living: "know yourself." These two words became his passion and his singular contribution to Western culture.
Do you know what you don't know?
How do we know ourselves? Through the "Socratic" method of questioning our assumptions and truth claims. His method began by professing ignorance of the truth, and seeking it through dialogue. He would seek a definition of the truth in question, test it by common experience, and deduce consequences.
For instance, consider this abbreviated record of a conversation between Socrates and a man named Meno:
Soc. By the gods, Meno, be generous and tell me what you say that virtue is. . . .
Men. There will be no difficulty, Socrates, in answering your question. Let us take first the virtue of a man--he should know how to administer the state, and in the administration of it to benefit his friends and harm his enemies; and he must also be careful not to suffer harm himself. A woman's virtue, if you wish to know about that, may also be easily described: her duty is to order her house and keep what is indoors, and obey her husband. Every age, every condition of life, young or old, male or female, bond or free, has a different virtue: there are virtues numberless, and no lack of definitions of them; for virtue is relative to the actions and ages of each of us in all that we do. And the same may be said of vice, Socrates.
Soc. How fortunate I am, Meno! When I ask you for one virtue, you present me with a swarm of them, which are in your keeping. Suppose that I carry on the figure of the swarm, and ask of you, What is the nature of the bee? And you answer that there are many kinds of bees, and I reply: But do bees differ as bees because there are many and different kinds of them; or are they not rather to be distinguished by some other quality, as, for example, beauty, size, or shape? How would you answer me?
Men. I should answer that bees do not differ from one another, as bees.
Soc. And if I went on to say: That is what I desire to know, Meno; tell me what is the quality in which they do not differ, but are all alike--would you be able to answer?
Men. I should.
Soc. And so of the virtues, however many and different they may be, they have all a common nature which makes them virtues; and on this he who would answer the question, "What is virtue?" would do well to have his eye fixed; do you understand?
Men. I am beginning to understand; but I do not as yet take hold of the question as I could wish.
[Socrates continues through ten pages of questions regarding the various nature of various virtues, none of which Meno is able to answer.]
Soc. Then begin again, and answer me. What, according to you and your friend Gorgias, is the definition of virtue?
Men. O Socrates, I used to be told, before I knew you, that you were always doubting yourself and making others doubt; and now you are casting your spells over me, and I am simply getting bewitched and enchanted, and am at my wits' end. And if I may venture to make a jest upon you, you seem to me both in your appearance and in your power over others to be very like the flat torpedo fish, who torpifies those who come near him and touch him, as you have now torpified me, I think. For my soul and my tongue are really torpid, and I do not know how to answer you; and though I have been delivered of an infinite variety of speeches about virtue before now, and to many persons--and very good ones they were, as I thought--at this moment I cannot even say what virtue is.
The point is not what virtue is, but that we cannot know what virtue is unless we know ourselves first. Objective, empirical, coldly logical speculation does not achieve truth. But logic is a useful tool in defining the truth we must experience personally.
The Socratic method has been used for twenty-three centuries to arrive at clear definitions, to expose fallacious assumptions, and to discover truth. But this is just the beginning of Socrates' contribution to our culture.
How's your soul today?
Socrates' most important belief about you and me is that we are a soul, an eternally-significant person who must care for our spiritual lives as our highest priority in life. Before Socrates, the spiritual nature of human life was a means to an end--the more we pleased the gods, the happier and richer we might expect to become. While there were isolated philosophical movements who sought to cleanse the soul from its prison house (cf. the Orphics and Pythagoras), they never captured the popular imagination. Socrates did.
He was a "gadfly" on the Athenian culture of his day, consistently insisting that we know and practice only the good. Socrates (naively) believed that the soul will always do good when it knows the good. And he believed that our quest for the good mirrors the ontological existence of the Good, an objective right and wrong which exists independent of our subjective experiences.
And so Socrates wants you and me to seek always to do the good. How? By investigating rationally all claims to the good, to see if they are built upon a truthful and objective definition and reality. And then by applying this reality to our lives, whatever its cost.
For example, when Socrates was condemned to death unjustly by the Athenian courts as a corrupter of their youth (actually he exposed the corruption of their parents), he was faced with a moral dilemma. He could easily have escaped his prison cell with his life. But his rational investigation of this option led him to a certain conclusion: if every person condemned by the courts were to flee his sentence, a just and ordered society would be impossible. If it is wrong for others to flee justice, he could not flee justice. And so he must die.
Socrates drank the hemlock which ended his life because he believed this to be the objectively right thing to do. He sought and lived for the good, always. And his example would forever change the way Western thinkers sought to do the same.
Socrates taught our Western civilization that there is an objective truth, and that we can know it. Jesus agreed, though for very different reasons and in a very different way: "I am the way and the truth and the life. No one comes to the Father except through me" (John 14:6). To the degree that we admit and recognize the truth about God, others, and ourselves, we can live in the light of our Father's word and will. If there is an area of your life which contradicts or ignores the truth of God's revelation and purpose for your life, today is a wonderful day to resubmit yourself to "the Truth" himself.
Next we will study the influence of Socrates upon Plato and Aristotle, and through them, on our lives today. For now, know that an emphasis on objective truth, determined rationally and then experienced personally, has been the single most important intellectual foundation for the Western world. And that foundation was first built by a little son of a stonecutter.
He has not finished carving our world, yet.
A broad thinker and the world he left us
A newspaper article described change this way: "Try as you will, you get behind in the race, in spite of yourself. It's an incessant strain, to keep pace . . . and still, you lose ground. Science empties its discoveries on you so fast that you stagger beneath them in hopeless bewilderment. The political world is news seen so rapidly, you're out of breath trying to keep pace with who's in and who's out. Everything is high pressure. Human nature can't endure much more!"
Sounds like yesterday's news, doesn't it? It is--from the Atlantic Journal, June 16, 1833.
Despite all that has changed about our culture, our most basic questions remain unanswered today. What happens when we die? How can we live meaningful lives? What are the best ways to raise our children? How do we govern ourselves as individuals and as a nation?
The most influential answers ever proposed for these perennial, ultimate questions came from a man nicknamed "the Broad," and his most unruly pupil. And everything else in Western philosophy is largely a footnote.
Aristocles was born in 427 B.C., and later given the nickname Plato (meaning "the broad," apparently owing both to the size of his intellect and his girth). To call him the son of aristocracy is to understate the case. His family traced themselves to Poseidon, god of the sea, and Solon the lawgiver. When your ancestors rule most of the surface of the planet and the laws of all mankind, you're under pressure to make something of yourself. And Plato did.
As the story goes, he was twenty years old, dark and handsome, when he met Socrates. Immediately he changed his life's ambition to philosophy. So much for family expectations. But no one knew the historic significance of this decision, least of all Plato.
Sparta defeated Athens in 404 B.C. Plato left his conquered hometown, disillusioned and bitter. For several years he wandered across Greece, Italy, Sicily, and Egypt, meditating constantly on the thought of Socrates. He finally returned home to take up the work of his former teacher, founding the first great philosophical school in Western history. This school was named the Academy (for the grove of trees under which it met; does this make them shadetree philosophers?)—hence "academics" today. Plato spent the rest of his life at his school, active in teaching and writing to his death in 348 B.C.
His writings have all been preserved, but little of his oral teaching was recorded. His writing reads like dialogue, however, as it is in the form of conversations between Socrates and others. His literary skills were considerable, but not systematic.
One of the great struggles in understanding Plato is the existence of apparent philosophical contradictions recorded in these dialogues. The other is in knowing when Plato is preserving the ideas of Socrates and when he is putting his own thoughts in Socrates' literary mouth. While questions remain about some of his ideas, no doubt remains about his influence.
We're only a shadow of ourselves
Plato thought that you and I inhabit a world which is but a shadow of the real world. Here's why.
We're in bad hands
Plato was convinced by Socrates that the objective Good exists. But he couldn't find it anywhere in this corrupted, decadent world. And so he concluded that it must exist someplace outside the material universe. But where? Borrowing from the Pythagoreans their Orphic belief that the soul is a fallen, preincarnate god, he found his answer.
According to Plato, a world of eternal, unchanging, perfect realities exists, but in the realm of ideas, not physicality. This "place" he called the world of Forms or Ideas. It must by definition be separate from the sensible world, and is known only to the intellect. These Forms are unchanging realities, and the only objects worth knowing.
What of our changing, non-ideal (literally) world of experience? It is only a shadow of the Forms, a physical and thus imperfect reflection of the Ideas it represents. The way to escape the shadows and experience the Forms is through philosophy (naturally), specifically by seeking the true, universal definition of a thing or experience. When we understand an entity in its perfect, unchanging essence, we have glimpsed the Form which it reflects.
We need an example, preferably as mundane as possible. So, consider the fingers with which you type on your computer. What is unique or at least unusual about your hands? (fingerprints, shape, etc.). What is the unchanging essence of the "perfect" hands? You are this moment contemplating the Form of hands, of which your physical appendages are but a poor representative. Just as a shadow is not the real thing, so your hands are not real in themselves. Alas, they only copy the ideal hands you have discovered by philosophical reflection. And they are not the way you wish they were (ask any arthritic).
How did we get in this sorry state of affairs? Remember Orpheus' strange idea that our souls "sinned" in their pre-mortal existence and are punished by being put in such fallen hands (and eyes, and ears). Pythagoras believed Orpheus, and Plato believed Pythagoras. You may not believe Plato, but millions of people for eight centuries did.
Here is Plato's most popular illustration of our world of shadows. Imagine that you are exploring some caves in a park. You walk into one very strange cavern, finding inside a group of people who are chained to the back wall. Their captors have arranged things so that these unfortunate people cannot turn their heads to see behind themselves. Thus they do not see you, or even know that a "you" might exist. The only world they can see is the back wall they face. Behind them roars a giant fire, casting their shadows on this wall. Because they have lived their entire lives seeing only these shadows, they assume them to be all the world there is. But you know better. You want to unchain them and show them the larger world they cannot see. So did Plato.
How do we rattle such chains?
Remembering what you know
Plato is sure that your soul not only lived once in the world of Forms, but can remember it (with a little help). When you contemplate the beautiful, or reflect on the ideal, your soul is reminded of that perfect Idea it once knew. This is the theory of "anamnesis" ("remembering"), and it constitutes the first epistemology (theory of knowledge) in Western history.
To help your soul remember its roots, you need a little discipline. Plato offers these helpful hints. He thinks that your intellect is the rightful ruler of your soul, aided with the higher emotions (such as love, nobility, sacrifice, and the like). However, the lower emotions of lust and pride want to hijack the whole enterprise. So you must discipline your soul through the use of reason and logic, temperance and virtue
Plato likens your soul to a charioteer (your mind) and two horses (the higher emotions, which help steer, and the lower emotions, which want to take the whole thing into the ditch). So long as your thoughts and feelings take the high road, so to speak, all is well.
Let's try this theory out. Think for a moment about the table at which you are sitting, or last sat. Who thought of such an odd idea as a piece of wood held up by four others? How did he or she come to design the first such thing? What design did the builder attempt to execute? Probably a more perfect table than you are seeing or remembering right now. That "ideal" table was composed of a perfect rectangle, supported by perfectly designed and created legs. But such perfection is impossible in this world of imperfect wood, nails, and hands.
So where did such a perfect design come from? Not visual, physical experience, for no such entity exists. If Plato is right, the first architect of the first perfect table contemplated the idea of "tableness," if you will. Such contemplation caused his or her soul to remember the "idea" of the perfect table. The result was a design only imperfectly executed in wood.
The only hope for us in this flawed world is that our souls can also remember the unchanging moral standards which regulate life in the world of Forms. An absolute morality, learned from Socrates, permeates Plato's world view. But that morality has no reference in God or our personal relationship with him, for reasons we'll soon examine.
Why does any of this matter to you and me today? For this simple and important reason: if Plato is right, the way Christians see God, themselves, and their world is wrong. Tragically, for nearly five hundred years the church saw God through Plato's eyes, not Plato through God's. And we're still paying for that mistake today.
Let's see why, and how.
Working with rusty nails
Plato's way of seeing the world works itself out in theology and everyday life with disastrous consequences. First, think about where all of this puts God.
God is only an idea
If physical reality is a flawed shadow, then a perfect God cannot be definition have any part of it. If he made it with all its imperfections, he clearly is imperfect as well.
And so Platonic thought relegates God to the realm of ideas only. He can have nothing to do with this shadowy place. The very idea that he would intervene in the natural world you and I must inhabit is absurd by definition. The miraculous is rendered impossible, and any hope you and I have to know God while in this shadowy cave is dashed. Think about him, but don't try to experience him personally. Doesn't much of our culture today agree?
If Plato is right, God is a figment of your imagination, literally. Your idea of God may be very different from mine. Who's to say who's right? And what difference does it all make anyway? Can you see why Greek philosophers had such little interest in personal religion? And why our Western culture has a built-in suspicion of it as well?
Growing up, I thought that religion was a crutch for cripples. So did Plato. What neither of us realized is that we're all crippled. And Plato's God is no help at all.
How things got this way
So, how did this cave of shadows come to exist? It seems that God created a divine craftsman, a figure who made both souls and bodies from pre-existing materials. This craftsman did the best he could, but he had rusty nails and warped two-by-fours to work with. This material world is the source of evil in our lives--it is irrational, chaos in perpetual movement. And there's nothing either God or his carpenter can do about it.
The divine craftsman modeled his work on the Forms which exist in the world of Ideas, but he could make only imperfect copies of them. This is why when you contemplate a table you can imagine the "tableness" he was attempting to reproduce. Your soul remembers the Ideal table and is drawn from this chaotic cave of shadows to the real world of Forms.
Here's what Plato's theory of creation means for Christians: this world is a bad place, and you want to spend as little time here as possible. You want to break the philosophical chains which tie you to the shadows you see, by thinking about the world you cannot. You cannot change the world, so don't try. Just don't let it change you.
This is the most popular definition of spirituality I know today. Retreat from this fallen, sinful world. Spend as little time in it as possible. Live at the church, raise your kids there, go to school there, socialize there. Shop from the Christian Yellow Pages; listen only to Christian music; read only Christian books; have only Christian friends. And somewhere Plato is cheering.
Didn't Jesus warn us that salt is no good in the saltshaker?
A philosopher needs his island
How would Plato rule a country, given his ideas about ideas? Rather sternly, it turns out. Just as the soul is governed by reason, so society should be governed by the reasoners. The philosophers make up the "guardian" class and order the government and its citizens. They are aided by the "warrior" class (akin to the higher emotions we saw in Plato's epistemology), who work in close cooperation with the guardians to keep the masses in line.
The "working" class (like the lower emotions) must be governed closely. They do the farming, manufacturing, trading, and other mundane work which makes the city-state possible. And so they feed the guardians and warriors who rule them.
How are we to produce these classes? Guardians are deprived of all natural marriage, private property, or family life. They are mated to other guardians. Their offspring never know their parents, but grow up in a general nursery and so are protected from all concerns but the rational.
To make all this happen, the city-state should be located on an island, with all foreign contact strongly discouraged. And you thought democracy was flawed.
The best thing about Plato's theory of politics is that it was never enacted. Makes our politics look better, doesn't it?
Ignore the shadow of the shadow
What of aesthetics, a theory of art? Plato saw all visual art as a distraction. After all, if an apple you can see is but a shadow of "appleness," then a painting of that apple is a shadow of a shadow. A royal waste of time.
But Plato knew that art, for all its flaws, has great influence on our souls, especially the lower emotions. So he wanted it tightly censured. And music most of all, since it bypasses the eyes and goes straight to the soul. If he thought so poorly of the ordered, mathematically-oriented music of his day, what do you suppose he'd think of rap?
Plato was more helpful when he did science. He was convinced that the earth is not stationary, but revolves around an axis. It would take the Western world nearly two millennia to agree. He urged the standardizing of weights and measures, and was sure that 365 days make a year. If only he'd stuck to science and left politics alone.
The central tradition of Western thought owes its very existence to Plato. He was the true philosopher of beginnings, since he started the serious discussion of almost every great philosophical question. He wanted us to focus on our souls, and to live out the unchanging standard of morality he first learned from Socrates.
But his God bears no practical relationship to our lives. His world of Forms has no connection with this physical universe, except through his epistemological speculations. The world wanted a more concrete explanation. Enter Aristotle.
The biological philosopher
We are truly in the Information Age. But we're not the first people to center our lives and culture around the accumulation and transmission of such. The second great thinker in Western history would have loved the Internet. Except that he already knew more than it does, or wanted to. As we continue to consider the reasons we think as we do, let's meet Aristotle.
The greatest of Plato's pupils was the most unlikely. Aristotle (384-322 B.C.) was the son of a doctor and the heir of a long family tradition in medicine. Not exactly the career pursuit a teacher would suggest who believed the physical is but a shadow. He grew up in Stagira, a city in Chalcidice on the north coast of the Aegean Sea. When he was eighteen he entered Plato's Academy, and stayed there for twenty years (until Plato's death in 348 B.C.).
Sometimes Aristotle maintained an excellent relationship with his teacher. On other days he would linger after lectures and challenge Plato's ideas and reasoning. Plato referred to him as the "mind" of the Academy. When Aristotle once conducted a sharp polemic against the master, Plato compared him to a filly that kicks the dam whose milk it drank. And when Plato's favorite pupils were absent one day, Aristotle argued so ruthlessly with the 80-year-old master that Plato was obliged to remain away from his own Academy for three months. Tough stuff, philosophy.
At Plato's death, Aristotle was incensed that he was not put in charge of the Academy (one wonders why he was surprised). Plato's nephew got the job instead, proving that academic politics haven't changed. And so Aristotle stormed off, moved to the principality of an old student of his named Hermias, married his niece, and wrote a noble poem when Hermias was later betrayed and crucified. From there he moved to the coast of Asia Minor to study marine biology. And by the way, for three years (from 343-340 B.C.) he tutored the heir to the throne of Macedonia, a young man named Alexander.
In 335 Aristotle returned to Athens to found his own philosophical school, the Lyceum. Here he built the first important library in Greece, with a large collection of maps and a natural history museum. Given his family background, it is no surprise that his curriculum was broader than Plato's Academy, including natural sciences, biology, literature, psychology, and the new science of logic.
Unlike Plato's artistic dialogues, Aristotle's works were composed of his straightforward, tightly reasoned lectures. He gave these lectures while walking about the spacious gardens of the Lyceum with his students while they discussed various subjects together. Hence the "peripatetic" method of teaching (from the Greek words for "to walk about"). Many preachers are peripatetics and don't even know it.
In 323 B.C., when Alexander the Great died and an anti-Macedonian sentiment swept the country, Aristotle was forced to abandon his Lyceum. He fled the country, and died the next year.
God, the universe, and all related subjects
Aristotle's major work was nothing much—just gathering all the learning of the past and present, in the fields of science, philosophy, rhetoric, law, and literature, and organizing this knowledge into meaningful patterns which would be available to posterity. And we thought Plato was broad.
The result was philosophy developed on the largest possible scale. Aristotle's career established the great divisions of philosophy which are still accepted today, and he made enduring contributions in each of them. Let's look at these contributions, each in turn.
Let's be logical
If we are going to organize all learning into one system, we will need a strategy. And so Aristotle's first contribution to philosophy and Western thought was to state the laws of logic as we know them today. He studied the structure of rational thought, seeking to define those essential principles which sustain all reasoned inquiry. And he succeeded.
We all employ three basic axioms whenever we think in ordered ways. First, we use what Aristotle called the law of identity: A is A, and it must remain so. In other words, we begin by identifying the reality we are seeking to understand. We name it, quantify it, qualify it. We first want to know what it is, and how it relates to the rest of reality.
Then we move to the second axiom of reason: the law of contradiction: A is B, or it is not B, but it cannot be both. Whenever we identify something, we also identify what it is not. And it cannot be both, or reason breaks down. The page on which you are reading these words is either visible or it is not. If we think it is both, we cannot think about it at all.
Now we're ready for the last axiom of logic: the law of the excluded middle: A is B or it is not B, but it cannot be both at the same time. A statement must be either true or false within a given logical context. We must choose.
These laws of logic have sustained rational inquiry from Aristotle to today. This effect has been both very good and very bad, for reasons we'll soon investigate.
"The form be with you"
The logical approach Aristotle brought to the work of philosophy was a distinct departure from Plato's dialogues on scattered subjects. But his greatest break with his master came not in strategy but in substance, literally.
Remember that Plato was convinced by Pythagoras that there is a world of Forms or Ideas, distinct from this physical world, and that this world is but an imperfect shadow of that which is real. This ontology was the foundation for Plato's approach to the soul, the physical universe, aesthetics, and the future.
Aristotle rejects this essential premise. Completely. He is certain that the Form, such as it is, is to be found in the material world itself. Rather than being a shadow of the real, the physical universe is the real. Why did Aristotle come to this monumental shift of worldviews? And why does it matter?
Aristotle begins in his usual logical way. Rational beings must know objective truths, or they are not rational. However, the Forms cannot be known objectively--they are the product of a speculative philosophical system, not empirical experience. And so the primary realities of life must be the individual things we perceive. As a result, the Forms (such as they are) must be contained in the objects themselves.
In this view, individual concrete entities are real and scientifically knowable. Aristotle calls these entities the "substance," the thing which actually exists. He takes Plato's Forms to describe the unchanging essence which gives the thing its definition and purpose. As a result, things can change in quantity, quality, and position, but they cannot change in themselves because of their form.
And so Aristotle's ontology incorporates Plato's insistence on objective truth and values, as it was learned from Socrates. He explains how the world can change (cf. Heraclitus) while affirming unchanging values and timeless truths (cf. Parmenides). And he makes it possible for philosophy to be relevant to the observable world of real life experience.
One example of this relevance is Aristotle's fascination with biology. He was the first to construct a system for naming, categorizing, and relating all living forms. Another example is his view of the universe. He saw the observable universe as eternal and all-embracing, with nothing (such as a world of Forms) outside it, and theorized that it is hierarchically ordered and subject to causation in every respect. His understanding of physics was formative until well after the time of Copernicus--for centuries, the heavenly bodies revolved around the earth in perfectly elliptical, rational orbits. Or so the world thought. Such theories and many others were motivated by Aristotle's shift from the unseen Forms to the observable Substance of life.
How does this new perspective change things? In every way. If Aristotle is right, there is no "spiritual" realm to be separated from the "secular." God is not distant from this material universe. Spirituality is best developed by studying the empirical things which surround us. Ministry happens by reaching the world we can see, not by escaping to the world we cannot. We'll watch this philosophical shift as it works itself out in monumental ways across Western culture.
A moving god
Some of the most intellectual facts have the most mundane explanations. For instance, most Christians do not know that the letters of Paul are arranged as they are for this deeply spiritual reason: they go from longest to shortest. Many people do not know that "Bible" comes from Byblos, the town where ancient paper was harvested and processed, so that the Holy Bible is simply the Holy Book. And many theologians and other Christians use the word "metaphysics" without ever knowing its deeply intellectual etymology--it is so named simply because Aristotle's writings on this subject were placed after ("meta") his writings on physics in his collected works. Philosophical trivia is such fun, isn't it?
When we reach Aristotelian metaphysics, we come to the most significant single subject in his thought relative to Christian faith. Remember that Aristotle believed the physical universe acts according to predictable laws of cause and effect. All substances are in constant motion. So, he asked himself, where did all this motion begin?
It seemed reasonable to Aristotle to suggest that motion requires a mover. All observable experience suggests that this is so. And so an Unmoved Mover must be the first cause of all other motion. This Mover would be purely immaterial in nature, on the order of Mind, since all material things require something else to begin their motion. Unlike Plato's Forms, it can cause physical reaction by direct involvement with the material universe, since the Form is in the Substance.
And so Aristotle believed that a Mind exists, self-sufficient and containing all knowledge and motion within itself. This Unmoved Mover would be impersonal, with no capacity for individual relationship with us. We can accept the existence of this God, but we cannot know him (or it).
When we apply Aristotle's laws of logic to his theology, we soon see how incompatible his metaphysics are with Christian faith. God cannot be three and one, for this is a contradiction; Jesus cannot be fully God and man, for the same reason. If laws of logic prevail, the Bible cannot be fully inspired and yet the product of human personality; God cannot be sovereign over the future while allowing us free will. But these denials of Christian belief are no problem for Aristotle, for he holds none of these beliefs.
When a theologian uses non-contradiction as the test for all truth, know that Aristotle is pleased. But God may not be.
Life is hot air
From theology, Aristotle soon moved to ethics. His work comprised the first comprehensive study of morality in Western history. He was primarily concerned with finding the underlying purpose for human existence. And he (and millions after him) thought he succeeded admirably.
Aristotle observed that all people aim at eudaemonia--well-being or exalted happiness. (Note the influence of this idea on Thomas Jefferson and the Declaration of Independence.) Aristotle believed that the life of reason leads to this happiness, manifested as a holistic, complete life. For him, virtue is a settled disposition of character and right behavior. The life of reason flourishes when we follow a balanced course, the "golden mean."
And so Aristotle wanted us to feel anger, but not too much--righteous indignation, but not irrational action. He wanted us to feel sexual attraction, but not to the point of obsession. He wanted us to seek wealth, but not so much that we become overly materialistic. And so on.
Above all, he wanted us to contemplate life. Here we find perfection in the direct knowledge of the realities revealed to us by metaphysics, mathematics, and his philosophy of nature. The more we seek to understand perfection, as revealed in the imperfect world around us, the more our souls are elevated to eudaemonia. This idea would influence spirituality for more than a thousand years.
For Aristotle, the soul is the highest principle of life and being. It possessed no previous, disembodied immortality (vs. Orpheus and Plato). And the only part of you which lives beyond your death is the "separate reason," the highest part of your soul. Your soul operates in your body through the pneuma--a life-giving heat (literally "hot air"). By this active material principle, your soul influences your body.
And so with Aristotle we arrive at the "tripart" view of humanity which is still highly influential today--body, soul, and spirit. This is not at all the biblical view of mankind (which sees us as a whole being, variously described as body, soul, and spirit, but one creation). But it is the most popular today.
The drama made me do it
Like Plato, Aristotle thought art to be highly influential. Unlike Plato, he believed it to be valuable for our souls. Since the Form is in the Substance (the sensory world), artistic reflection on the world which surrounds us is good for our souls.
And so Aristotle wanted art to imitate life. He especially liked art which appeals to the emotions as well as the intellect. And he most especially liked art which helps to purge our spirits. This cathartic function of artistic expression is the highest purpose an artist can achieve, in Aristotle's view. Tragic drama is therefore the best art, for it operates psychologically to relieve us of the oppressive emotions of pity and fear.
This philosophy of art has become is one of the most influential aesthetic theories all time. It has been used to justify all sorts of artistic expression, and has itself been subject to significant critique. In short, it is by no means certain that an artistic cathartic experience relieves us of our emotions or the need to act them out. Much evidence indicates that such artistic experience actually creates in us an even greater desire to act out what we have seen the artist do.
Aristotle would say, "The drama kept me from doing it." Many psychologists today would say the opposite.
 Plato, Meno, trans. Benjamin Jowett (Indianapolis: The Bobbs-Merrill Company, Inc., 1949) 24-6, 35-6.