Point of Departure . Philosophy, according to Aristotle, begins in wonder. This approach might well describe how not only individuals but also cultures come to philosophize. It is difficult, however, for modern scholars to discover what first impelled the ancient Greeks to engage in abstract speculation; the same problems encountered in trying to understand Greek religion are encountered in examining philosophy, namely those concerning the scope of the term, the variety of differing practices, and the incompleteness of evidence.
Obstacle . Incompleteness of evidence is the single most significant obstacle to understanding early Greek philosophy. The earliest speculative thinkers of Greece existed during a period when literacy was rare. Their work sometimes took the form of poems performed orally and sometimes simply of conversations with their friends and acquaintances for which one must rely on transcriptions or quotations by listeners. Even in the case of authors who themselves wrote their opinions in books, only pieces— quoted or recopied by later authors—survive.
Terminology . The second problem one encounters in studying ancient philosophers is that of which thinkers should be considered under the rubric of “philosophy.” The term philosophia (love of wisdom) is said to have been invented by Pythagoras and was adopted by Plato and his followers. Many of the thinkers that later Greeks describe as the founders of philosophy, such as Thales, Heraclitus, Parmenides, and Anaxagoras, existed before the term itself was invented. By the time the term came into widespread use in the late fifth and early fourth centuries, its semantic range was itself a subject of contention among those calling themselves philosophers. While the Pythagoreans, and to a lesser degree, Plato and his followers, formed associations dedicated to speculative thought with a quasi-mystical bent, Isocrates claimed that the best form of philosophical knowledge was that of oratory, and that the philosophical life was one of political activism rather than abstract contemplation. A variety of other terms such as sophist, cynic, physicist, rhetorician, poet, doctor, and sage, was also used to describe many of the people who engaged in activities classicists now include in histories of philosophy; even so, many of these same thinkers engaged in activities that would be considered quite alien to the philosophical, including predicting eclipses, magic, astrology, diplomacy, reciting poems at festivals, and writing speeches for law courts. From an ancient point of view, however, Empedocles, for example, was not a philosopher who dabbled in magic, medicine, and poetry, but simply a wise man (or charlatan, depending on whom you asked) who understood the nature of the cosmos (both the natural and human universe) and used his knowledge to act for the benefit of individuals and communities.
Three Groups . Nineteenth-century scholars, following models established in antiquity—perhaps with an eye more to convenience than accuracy—had tended to divide ancient philosophy into three periods: a confident and scientific one, typified by “Presocratic nature philosophers” or “physicists”; a skeptical one, including the Sophists (and sometimes Socrates), who were concerned with human activities because the external world was unknowable; and a period containing the great synthetic work of Plato, Aristotle, and their schools, followed by a decline into scholastic quibbling and eclecticism. While this scheme of periodization is weak on chronological grounds (many of the so-called Presocratics were contemporary with Socrates and the Older Sophists), it is useful for the student trying to categorize and remember a large selection of unfamiliar thinkers.
Beginnings . Thales, traditionally classed as an Ionian physicist, was often credited with being the first philosopher, but since written records for seventh and sixth century Greece are spotty and unreliable, it is a claim difficult to prove (or disprove). Possibly, though, speculation of the type that was to evolve into philosophy, especially systematic enquiry into the natural world, began in Ionia in the late seventh or sixth century and grew out of two major sources: mythography, which had begun to systematize accounts of the gods and their roles in the creation of the universe and humanity; and Near Eastern and Egyptian science (especially astronomy), medicine, and divination.
Early Ionian thinkers had in common with modern scientists a desire for economical explanations of phenomena. In other words, they tried to bring orderly and simple explanations to bear on the diverse data of daily experiences. Some of them suggested that the variety of physical substances perceived arose out of transformations of a single substance, just as ice, steam, and liquid are forms of water. Others looked for a single ordering principle (usually divine and/or rational, but sometimes mechanical) to account for the regularities which appear in nature (for example, smoke rises but solid objects fall, or that the sun and planets disappear and reappear on fixed schedules).
Natural World . Most of preserved works of the Greek thinkers living in the eastern colonies of Ionia or the western ones of Italy were primarily concerned with the natural world, but their physical speculations were often accompanied by ethical ones. Heraclitus, Xenophanes, and Empedocles all were concerned with what is most valuable in human existence and the nature of the gods and the soul. The atomists, Democritus and Leucippus, derived from their physical conclusions about atoms theories of the best way to cultivate the tranquillity of the soul. Many of the Presocratics had an almost ascetic bent, extending (or perhaps influencing) the traditional Greek value of moderation to a greater level of austerity, condemning, variously, eating of meat, drunkenness, desire for physical pleasure, and loquacity.
Range of Interests . The thinkers who congregated in Athens, whether native or immigrant, included many whose primary interests were in ethics (the proper behavior of individuals), politics (the ordering of cities), and rhetoric (the use of persuasive language). The linguistic focus of early Greek thought began among the Presocratics but expanded considerably with later thinkers. Since people think and communicate by the means of words, to understand things correctly is equivalent to being able to give a correct account of them, and thus understanding things depends to a certain degree on precise use and knowledge of language. Both Socrates and the Sophists, therefore, discussed problems of language and definition, as well as moral and epistemological questions. Meanwhile, Plato and Aristotle had wide-ranging interests, including logic, physics, ethics, theology, biology, politics, rhetoric, and literature. They both founded schools that survived their deaths, and both have continued to influence philosophy to the present day.
W. K. C. Guthrie, A History of Greek Philosophy, volumes I-VI (Cambridge: Cambridge University Press, 1962-1981).
A. A. Long, ed., The Cambridge Companion to Early Greek Philosophy (Cambridge & New York: Cambridge University Press, 1999).
Francis E. Peters, Greek Philosophical Terms: A Historical Lexicon (New York: New York University Press, 1967).
H. D. Rankin, Sophists, Socratics& Cynics (London: Croom Helm, 1983).
Giovanni Reale, A History of Ancient Philosophy, volumes I & II (Albany: State University of New York Press, 1990).
J. O. Urmson, The Greek Philosophical Vocabulary (London: Duckworth, 1990).