Thales of Miletus

The Beginnings of Western Science and Philosophy

Patricia F. O'Grady

• Publisher: Routledge
• Year: 2017
• ISBN:
  9781351895361
• Edition: 1
• Topic: Philosophy
• Subtopic: Philosophy History & Theory

'What is the basic building block of the universe?' Thales of Miletus was the first to ask this fundamental, yet to be answered, question in the sixth century B.C. This book offers an in-depth account of the answers he gave and of his adventure into many areas of learning: philosophy, science, mathematics and astronomy. Thales proved that the events of nature were comprehensible to man and could be explained without the intervention of mythological beings. Henceforth they became subject to investigation, experiment, questioning and discussion. Presenting for the first time in the English language a comprehensive study of Thales of Miletus, Patricia O'Grady brings Thales out of pre-Socratic shadows into historical illumination and explores why this historical figure has proved to be of lasting significance.

1 Introduction

The origins of philosophy and science are exciting and intriguing, and the story of the pre-Socratics is jam-packed with fascinating characters, who proposed bold, exciting, sometimes outrageous and ridiculous theories to explain the events of nature. None is more exciting and intriguing than Thales of Miletus who was the originator of this new way of thinking.

Thales was born in the mid-620s B.C. in the prosperous Greek port-city-state of Miletus, which is now part of the lovely western coast of Turkey. The common belief of Thales’s world was that the events of nature and of man were planned and controlled by the gods of Olympus, a great family of gods and goddesses – let us say, actors in a play where every character had a role, a responsibility for one or more of the natural events. These all-powerful supernatural beings also controlled man’s fate, and while the citizens might entreat them, pray to them and sacrifice to them, the gods were superhuman, and often vengeful. Still, the world appeared to be ordered, functioning according to the will of the gods.

Then came the doubting, questioning Thales. Let us picture him sitting on the banks of the Maeander River, pondering and wrestling with the questions: ‘What is this World all about? If the gods are not the all-powerful beings most people believe them to be, what is it that brings about change, and what is the universe made of?’

And as he sat, pondering these questions, a ship, heavy in the water, berthed in the port. How could fully laden ships, heavier than water, stay afloat, and could that phenomenon be related to the Earth floating on water? How could the gods determine his prosperity when he knew that it resulted from his own endeavours? And if the gods were not the cause of natural events, what was the cause of eclipses? And why did the Sun rise and set further to the south in the winter, and rise and set further to the north in the summer? And how big was the Sun, and how big was the Moon? And how far away was that ship which had just risen above the horizon?

So many questions, but Thales was no mere dreamer. He was neither a mystic nor an eccentric, but a practical man, seeking answers to the questions about nature, and suggesting that sailors steer by Ursa Minor as a better means of navigation, advising the citizens how to overcome the danger of the Mede who threatened from the East, and making a packet of money when the conditions were right.

Because of his wisdom Thales was held in the highest esteem in ancient times, and was regarded as the most eminent, the most distinguished of the Wise Men of Ancient Greece. Diogenes Laertius recorded a letter purported to be from Anaximander, Thales’s contemporary, disciple and associate, to Pythagoras:

Let us who were [Thales’s] pupils cherish his memory, and let it be cherished by our children and pupils; and let us not cease to entertain one another with his words. Let all our discourse begin with a reference to Thales (D.L. 2.4).

My work on Thales discusses the very origins of philosophy and science. In its widest sense, philosophy was, and still is, the love, study or pursuit of wisdom, or of knowledge of things and their causes, whether theoretical or practical. Aristotle, the major source for this work, identified Thales as the first person to investigate the basic principles, the question of originating substances of matter and, therefore, as the founder of the school of natural philosophy.

In ancient times, Thales was held in high esteem for his many abilities and attainments, but present-day philosophers devote little in-depth research to his work. Although there has been a number of sketches or cameos of Thales by modern philosophers, historians, mathematicians, scientists, astronomers and mythographers, previous accounts of this innovative Ionian are inadequate because they are not comprehensive. Chapters in general philosophical works, by their very nature, are brief and, in articles, the topic is generally a single area of Thales’s expertise. My aim in this book is to describe and analyse all aspects of Thales’s endeavours and accomplishments, firmly to establish Thales as the first Western scientist and philosopher. It is, then, a reconstruction of his thought, work and attainments, and of the development of his hypotheses and ideas. It includes an evaluation of the anecdotal evidence, and a study of the political, commercial and social conditions of the times in which one man’s thoughts probed the phenomena of nature and initiated the first Western enlightenment.

Although there are no extant writings of Thales, there is a considerable and extremely valuable amount of theoretical and historical writing and commentary which is relevant to the investigation of his life and work. A number of pre-Socratics whose interests were similar to those of Thales, and who had written works to their credit, played key roles by recording their own and other opinions. It is highly probable that Plato and Aristotle had access to a number of Thales’s works which are no longer extant, but which could have recorded or discussed his views. Doubt will always exist but it is probable that Thales recorded the results of his investigations and, following an examination of the ancient reports, I draw attention to several areas of Thales’s work in which he would have been advantaged had he kept records of his work in progress, and severely disadvantaged had he not done so.

I propose a cyclic process of change that is consistent with the ‘watery thesis’¹ which Aristotle attributed to Thales. Attention is paid to the traditional explanations and common understandings of everyday things and events of the period, and these views are discussed in relation to the reasons which Aristotle thought may have been those which had influenced Thales (Metaphysics, 983 b22–25). Some ancient views are analysed because they relate earlier ideas which were still held in the archaic period and beyond. This is followed by a discussion of a number of geological and meteorological processes which can be identified as events within the cyclic theory of change. They are factors with which Thales could easily have been familiar. Aristotle’s report of Thales’s hypothesis could be explained and justified by observation of certain everyday phenomena, and some of the earlier notions about natural events retained their relevance into the archaic period when Thales lived and worked. Thales’s bold and original hypothesis was one which was reasonable for the times, and which would have been acceptable to those progressive individuals who had begun to consider new explanations.

Many modern philosophers are wrong in their assessment of mythological influences upon the thought of Thales. My discussion of Greek and other mythologies counters the views of those who claim that the theories of Thales were a regurgitation of the traditional tales, or that Thales did little more than retell the old stories, only omitting the gods. The factors which were influential in the development of Thales’s theories of nature were not the traditional concepts of his society. He advanced beyond the mere restatement of mythological belief. Testimony and argument are presented to justify dissociating Thales from the perception that his theory was little more than the old tales retold again. Thales’s hypotheses were new, bold, no doubt controversial, and certainly inspiring.

Those four words, new, bold, controversial, inspiring, surely describe the unprecedented ideas which Thales proposed about the Earth, especially his hypothesis that the Earth rests upon water. Most people would agree that this is a concept which is difficult to embrace. Aristotle’s criticism of the hypothesis clearly indicates that he had the same problem. The suggestion is offered that Thales’s intention was that land masses floated upon water, not that the entire Earth rested upon water which was as Aristotle interpreted it, or as his source suggested.

It is testified that Thales held a number of original ideas about the Earth. In a passage in De Caelo Aristotle seems to suggest that Thales recognized the sphericity of the Earth, a view which is repeated in the doxography. Some modern philosophers maintain that Thales could not possibly have comprehended the Earth as a sphere, but there is no ancient report that Thales believed the world to be flat and there are no compelling arguments to accept that opinion.

Thales’s theory of the phenomena of earthquakes is dissociated from the tale of a striding angry Poseidon, and remains consistent with his hypothesis of the Earth floating on water. Thales granted no credence to Olympian gods and goddesses in the cosmic organization. When one considers the new hypotheses which Thales put forward about the Earth, it is possible to accept the theses which I propose as most probably the ideas of Thales.

The notion of change was a major problem to the ancient philosophers. Thales, who first confronted the problem in a scientific way, proposed a unique view – soul was the cause of motion and change. He believed he had recognized a universal power which was the cause of motion, basing his hypothesis on his observation of the potentialities which are exhibited by the lodestone and amber. Crucial to that discussion is a passage in Plato’s Laws, where Plato engaged in a clever reconstruction of a question, even ‘a sleight of hand’, when he had the Athenian Stranger expound the view that ‘all things are full of gods’. This is the theory which Aristotle later attributes to Thales. Thales’s identification of a kinetic force which is necessarily inherent in water and which, therefore, is permeated throughout the entire cosmos, is a brilliant piece of original thinking, and one of the great theories in the history of science because it was the impetus that spurred others on to seek the cause of change.

Thales proposed a number of new astronomical theories about the cosmos. Ancient sources attribute to Thales the foretelling of the total solar eclipse of 28 May 585 B.C., and record the names of ancient philosophers who admired him because of his skill in astronomy. An argument is presented against the Saros and the Exeligmos, periodic cycles which could not possibly have been the method by which Thales predicted the solar eclipse of 585 B.C., and the lunar eclipse-solar eclipse period of 23½ months is proposed as a possible means by which Thales may have predicted the event.

It is testified that Thales determined the solstices, and that he recognized the length of the year as being 365 days. This is associated with attempts he may have made to devise a workable calendar. Thales is also credited with determining the ratio of the size of the Earth to the Sun and the Moon, and two methods he could have employed are discussed.

Herodotus did not accept the general belief of the Greeks that Thales assisted the Lydian king Croesus and his army to cross the Halys to encounter the Mede, Cyrus. Evidence exists to support the opinion that bridges already existed. Arguments are put forward to support the belief of Herodotus: Croesus took his army across the Halys over a bridge which then existed, just as Herodotus recorded the event.

Ancient testimony associates Thales with Egyptian and Greek mathematics, and with the introduction of geometry into Egypt. From the evidence, one may accept that Thales almost certainly spent some time in Egypt,² and one may further accept that he would have been amazed and intrigued by the wonders of that ancient land, by its monuments and temples, by the strange north-flowing River Nile, by the inundation, by the role and status of the priests, and by the practical art of land measurement in which the surveyors had become expert. The ancient texts attribute to Thales a number of discoveries in geometry and while it is realized that he did not develop proofs in the formal sense, (the miracle of Euclidean geometry being in the future), Thales was probably able to ‘prove’ his propositions and theorems through other methods.

The earlier chapters support the postulate that the hypotheses of Thales were both scientific and rational. Thales instigated a new way of looking at natural phenomena which did not rely on supernatural beings as the controllers of events. There was a distinct break between his explanations and the traditional views. I assess Thales’s conjectures by applying to them the formal techniques, the methodological tests, which are the accepted tools of modern researchers for determining the scientificity of hypotheses. When Thales’s hypotheses are evaluated in this way, his natural philosophy rates highly in most areas, and can be sustained by most of the criteria. It may be rightly claimed as the beginning of Western science.

A section on the Milesian School is important because of the probability that the practice of critical discussion, argument and conjecture, as factors in the development of the scientific method, originated with Thales in this School.

In the concluding chapter, the arguments that have been presented are drawn together. Despite the paucity of the sources, and the lack of original material from Thales, the substantial amount of incidental ancient text and traditional belief, together with my argument, discussion, explanation and opinion, confirm the claim that Thales’s hypotheses marked the commencement of reasoned scientific endeavour.

Two appendices follow the main body of the work. They deal with topics which are generally categorized as non-philosophical, and/or anecdotal but their inclusion serves particular purposes. They bear a close association with aspects of Thales’s life and work, and add to an understanding of this man who was philosophically enlightened, envisaged the ultimate in nature, and yet remained practical. Their inclusion completes the topic of Thales while leaving the argument concerning Thales uncluttered and in sharper focus. In addition, as a result of the analyses that are undertaken, the so-called anecdotal evidence appears as credible facets of Thales’s life and endeavours that tie together the unique characteristics of the man. Thales is recognized as more than the mere ‘shadowy figure’³ of Guthrie’s perception; he appears as an historical figure of substance, distinction, and significance.

Opportunities to travel abounded, and it is hard to believe that Thales would not have made use of circumstances that favoured journeys beyond Caria. Apart from the ancient testimony that Thales visited Egypt, there is little real evidence of visits to other countries. Despite that, there is a great deal of information to support conjectures that Thales would have travelled beyond his city-state of Miletus, and many feasible reasons to believe that he did. Thales was a man of insatiable curiosity, precociously investigating the phenomena of the cosmos and, at the same time, possibly making the most of any opportunities to make a drachma.

Investigation of the Seven Wise Men of Ancient Greece brought to light many interesting details. Not the least of these was the inauguration of the tradition, and the reconstitution of the Pythian Games at Delphi where the Seven are supposed to have assembled. Contrary to the opinion, commonly expressed by modern commentators, that Thales was admitted into the elite group because of his wise advice is the evidence that such was not the case. Thales was not identified as a Wise Man on account of his contribution to affairs of state, because his advice post-dated his appointment to that illustrious Seven.

Before continuing, I state my understanding that Thales was born in the latter half of the 620s B.C., that he lived for perhaps seventy-six or seventy-eight years, and that he died around the year 546, coinciding with the fall of Sardis in that year. His floruit is set as being 585 B.C., the year of the total solar eclipse, the Eclipse of Thales. The approximate dates for Anaximander are 611 B.C. to 545 B.C., and for Anaximenes approximately 585 B.C. to the first half of the 520s B.C. Based on the extant texts, the traditions that developed around each of the three Milesians, and the arbitrary method of dating, this is probably as accurate as it is possible to be.⁴

Because Thales was a Greek, a few Greek words have been retained, (in preference to reverting to the Latin), because an understanding of the terms is necessary to establish precisely what the sources recorded, and whether this could have been Thales’s intention. However, there is very little Ancient Greek in the book, and what there is, is clearly explained.

As already stated, Thales’s work has been discussed in numerous papers on astronomy, history, philosophy, and mathematics. What, then, is the purpose of this book?

First, in this work, Thales and his ideas are discussed in depth. My intensive research led me to the realization that Thales’s ideas have not previously been fully analysed in relationship to other factors, and warranted the consideration of different explanations. I have assessed the views of modern scholars, but have arrived at my own opinions.

My work differs from commonly held views and explanations in a number of ways: a detailed examination of the possible sources led to an extensive list of probable and possible sources on Thales for Plato and Aristotle; Thales’s watery thesis is more fully developed in relationship to commonly held ideas; Aristotle’s report of Thales’s supposition that all things are derived from water is analysed; and some commonly held beliefs which Thales may have believed justified his new hypothesis are discussed in their context. Empirical factors are explored. I examine Aristotle’s report that Thales held that the Earth rests on water; Aristotle was troubled by this belief and I suggest that he may have misunderstood Thales’s intention. I argue that the belief that ‘all things are full of gods’ can hardly have been part of Thales’s hypotheses, and discuss Plato’s sleight of hand when he extended a suggestion that ‘all things are full of gods’ to a full-blown theory, which Aristotle then attributed to Thales. The Saros and Exeligmos cycles are discounted as possibilities for the prediction of solar eclipses in the sixth century B.C. and a previously unexplored lunar eclipse-solar eclipse cycle is proposed. The flat Earth theory for Thales is refuted, there being no ancient evidence to support it. An argument is pursued in favour of the view of Herodotus that Croesus led his army acr...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• Preface
• Acknowledgements
• List of Abbreviations
• Note on the Sources
• 1 INTRODUCTION
• 2 THE WRITINGS OF THALES’ AND ‘ARISTOTLE’S POSSIBLE SOURCES FOR THALES’
• 3 THALES … SAYS THE ’APXH’ IS WATER
• 4 ARISTOTLE ON THE ’APXH’ OF THALES AND SOME TRADITIONAL EXPLANATIONS OF PHENOMENA
• 5 THALES AND MYTHOLOGY
• 6 NEW IDEAS ABOUT THE EARTH
• 7 ALL THINGS ARE FULL OF GODS
• 8 NEW IDEAS ABOUT THE COSMOS
• 9 CROSSING THE HALYS
• 10 THALES THE MATHEMATICIAN
• 11 SCIENTIFICITY AND RATIONALITY
• 12 CONCLUSION
• APPENDIX A
• APPENDIX B
• Selected Bibliography
• Indexes