Western Philosophy – The Beginnings of Rationalistic Thinking

By John G. Messerly, Ph.D. | 21 March 2016
Institute for Ethics & Emerging Technologies

The School of Athens, 1509–1511, fresco at the Raphael Rooms, Apostolic Palace, Vatican City. (Credit: Raphael / Wikimedia Commons / Public Domain)

The word philosophy comes from two Greek roots meaning “the love of wisdom.” Thus philosophers are (supposed to be) lovers of wisdom. In the western world, philosophy traces its beginnings to the ancient Ionian city of Miletus, the richest city in the ancient Greek world. There, on the eastern edge of the Mediterranean in the sixth century B.C.E., the Greeks began to systematically apply human reason to questions concerning nature and human life without reference to the supernatural.

The first Greek philosophers were interested in the question “what is the world made of?” Thales (c.585 B.C.E.), the father of Western philosophy, argued that the earth was made of water, although his successors rejected his argument. How, they wondered, could cool and wet water be the basis of hot and dry things? What’s important for our purposes isn’t the specifics of these arguments, but that for the first time in recorded history hypotheses were being advanced which were subject to rational criticism.

Subsequent thinkers maintained that physical reality was composed of a boundless (Anaximander), air (Anaximenes), fire (Heraclitus), the four elements (Empedoles), or an infinite number of seeds (Anaxagoras). Both monism—the view that one kind of thing comprises reality—and pluralism—that many types of stuff comprise reality—encountered difficulties. Monism couldn’t account for plurality, and pluralism couldn’t account for unity.

Greek thinking about the nature of the physical world culminated with Democritus (460-360 B.C.E.) and other Greek atomists, who argued that all of reality was made up of empty space and tiny, solid, indestructible atoms. This theory provided a theoretical solution to “the problem of the one and the many,” by postulating a qualitative singularity and a quantitative plurality. Material things were identical regarding the qualitative nature of their atoms, but differed in the number and configuration of those atoms.

This theory also resolved the “problem of change,” the paradox of how something changes into something else and yet remains the same. To understand this problem, consider the following. How are you now both the same person and a different person from when you were a small child? If you are the same, then you aren’t different; and if you are different, then you aren’t the same. In answer to this conundrum, Heraclitus (c. 500 B.C.E.) proposed that everything constantly changes. Parmenides (c. 515 – 450), on the other hand, asserted that permanence was the fundamental reality, and he used Zeno’s famous arguments against the possibility of motion to support his views.

Zeno (c.490-430) had argued that the swift Achilles could never pass a front-running tortoise in a race because, by the time Achilles reached the place where the tortoise was previously, the tortoise would have moved ahead to some further point. When Achilles reached that point, the tortoise would have moved further on again, ad infinitum. So Achilles could never pass the tortoise and motion, a kind of change, was impossible. However, because we ordinarily assume motion is possible, the atomists and pluralists rejected the views of Parmenides and Zeno.

The Atomists argued that atomic transformations account for our perception of change. In reality the number and configurations of atoms changes, but their underlying qualities don’t. What we perceive as change is in fact quantitative transformation at the atomic level. In little more than a century, rational discourse alone, without the benefit of experimentation, had advanced the argument remarkably.

But atomic theory wasn’t the only achievement of Greek rationalism. As Greek influenced spread throughout the Mediterranean over the next few centuries, its accomplishments were most impressive. Hipparchus mapped the constellations and calculated the brightness of stars, and Euclid produced the first systematic geometry. Herophilus argued that the brain was the foundation of intelligence, and Heron invented gear trains and steam engines. Eratosthenes calculated the circumference of the earth with surprising accuracy, mapped the earth, and argued that the Indies could be reached by sailing west. (Yes, ancient scholars knew the earth was round.) Moreover, the accomplishments of Pythagoras the mathematician, Archimedes the mechanical genius, Ptolemy the astronomer, and Hippocrates the physician are legendary.

In Alexandria, where over the course of seven centuries the rationalist spirit flourished, the great library and museum held much of the knowledge of the ancient world. But this rationalistic spirit never seized the imagination of the masses and, in 415 C.E., the mob burned the library down. At the time, the greatest mathematician, scientist and philosopher at work in the library was a woman named Hypatia (c.370 – 415).

Unfortunately Alexandria in Hypatia’s time was in disarray. Roman civilization was in decline and the Catholic Church was growing in power. Cyril, the archbishop of Alexandria, despised Hypatia because of her friendship with the Roman governor and her place as a symbol of rationalism and paganism. On her way to work in 415 C.E., she was met by a fanatical mob of Cyril’s parishioners. In his book Cosmos, Carl Sagan describes the scene thus: “They dragged her from her chariot, tore off her clothes, and, armed with abalone shells, flayed her flesh from her bones. Her remains were burned, her works obliterated, her name forgotten. Cyril was made a saint.”

Though the pursuit of knowledge continued in the Middle East and in Eastern civilization, Western civilization would soon plunge into the dark ages and await the Renaissance, more than a millennium in the distant future, for the rebirth of the rationalistic spirit which began in ancient Greece. We can only speculate as to the increased extent of our scientific knowledge today had the spirit of this investigation continued unabated.

Western Philosophy Today

The ancient Greeks made no distinction between rational, philosophical, and scientific thinking. When Thales or Democritus practiced what we would today call physics or chemistry, these disciplines were still parts of philosophy. As the centuries proceeded and human reason discovered more about various branches of knowledge, the sciences formed their own distinct disciplines. However, this is a relatively recent phenomenon. Newton, for example, considered his revolutionary seventeenth-century work in physics to be natural philosophy. The natural sciences as distinct disciplines are recent, and the social sciences even more so. For example, economics and became an independent discipline in (roughly) the early nineteenth century, psychology in the late nineteenth and early twentieth centuries, and sociology in the early twentieth century.

Today, in the colleges and universities of the Western world, the residual, unanswered, and timeless questions which don’t fall within the specific purview of other disciplines comprise philosophy’s domain. Therefore some of the most difficult questions, for which there are as yet no definite answers or methodology, remain for philosophers to ponder. For example: Is the belief in a God reasonable? What is knowledge? Do we know anything for certain? What is the ultimate nature of reality? Why is there something rather than nothing? What is the nature of goodness, beauty, truth, liberty, equality, and justice? What is a good political system or fair economic system? What is valuable in art, music, or human conduct? What is morality? Are humans free? What is the meaning of science? What is the relationship between thought and reality? What is language? Are human beings entirely material? What is the meaning and purpose of human existence? These are just a sample of philosophical questions.

Most of these questions fall into a few basic groups. Metaphysics probes the nature of ultimate reality and revolves around the question, “what is real?” Epistemology studies the nature and limits of human knowledge and centers on the question, “what can we know?” Axiology explores the nature of the valuable in art, politics, and ethics and asks, “What is good?” And, since philosophy invokes reasoned arguments to support positions—rather than relying on faith, authority, tradition, or conventions—logic is that branch of philosophy that differentiates good arguments from bad ones.

In addition, many specialized fields exist within philosophy. There is philosophy of religion, mathematics, science, law, medicine, business, language, art, sport, and more. Note, one can practice any of these without philosophizing about them. You can be cleric, mathematician, scientist, lawyer, nurse, physician, business executive, linguist, artist or athlete without philosophizing about them. So philosophy is by nature a theoretical pursuit rather than a practical one. Philosophers ask: how do we know a religious claim is true? Does mathematics tell us about reality, or is it merely an arbitrary formal system? How do we know scientific theories are true? What justifies the use of legal coercion? What should the practice of medicine entail? Are ethical behaviors and profitable business compatible? Does language effectively communicate ideas? What makes good art? What purpose do sports serve? Any important part of human culture, the culture as a whole, or the ultimate nature of reality itself is ripe for analysis. Thus, philosophy is sustained, rational, and systematic reflection and analysis of the philosophical area in question.

In addition philosophers investigate the relationship between, for example, philosophy and psychology, literature, culture, gender, or history. Is philosophy independent of these forces, or does philosophy depend on them? Philosophers might study the history of philosophy in order to understand the evolution of ideas in history, or they might be more interested in the meaning of human history. Philosophers are also interested in theoretical issues in game theory, decision theory, and cognitive science, as well as practical issues concerning business, medical, and environmental ethics. The range of philosophy is enormous.

For the uninitiated, in order to get a grasp of the nature of philosophy, go into any library or bookstore and examine a work of non-fiction. Often, at the end of the work in question one finds a section entitled “Afterthoughts,” “Reflections,” “Postscript,” “Epilogue,” “What It All Means,” etc. There authors often move from their subject matter to reflect on the meaning or implications of their investigation. At that point, they are philosophizing.

Reprinted with permission from the author.

John G. Messerly received his PhD in philosophy in 1992. He has taught at St. Louis University and The University of Texas at Austin. He is currently an Affiliated member of the Evolution, Cognition, and Complexity Group localized at the Vrije Universiteit Brussel in Belgium, and an Affiliate Scholar of the Institute for Ethics and Emerging Technologies.

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  1. You probably shouldn't rely on pop-history for facts. The Library of Alexandria did not even exist in 415 AD, with accounts of it having been destroyed as early as Caesar's naval assault on Alexandria in 43 BC. What existed was the Serapeum, a temple that was once an annex of the Library but appears to have been a derelict building totally empty of books by the time it was demolished. The idea of Hypatia being flayed alive comes from a mistranslation of an account of her being stoned to death with roof tiles (referred to with the idiom "oyster shells") which originates in 1776.

    And seriously, Nixey, who relies on Gibbon and his ilk, long discarded as nonsense by modern historians? Come on, the "dark ages" were a myth created during the Renaissance, which by the way was not the only Renaissance of the Middle Ages, nor the first.


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