Listen to this article 
Anaximander of Miletus (l. c. 610 - c. 546 BCE) was one of the early Pre-Socratic Philosophers who lay the foundation for the deveopment of Western Philosophy. He was a student of Thales of Miletus (l. c. 585 BCE), recognized as the first philosopher of ancient Greece.
Thales holds this distinction as the first to initiate philosophical inquiry into the nature of existence in trying to define a First Cause for the creation of the world. Prior to his work, the world was thought to operate according to supernatural influences of the immortal gods and, even after he began his inquiries, this view of the operation of the world and human life prevailed. His inquiries, however, opened a path for others to widen and explore further, eventually leading to the process understood today as the scientific method. Anaximander was the first of Thales' students to move forward with this path of inquiry.
Thales claimed the First Cause was water which Anaximander rejected and replaced with the concept of the apeiron defined as "the unlimited, boundless, infinite, or indefinite" (Baird, 10). The apeiron was a cosmic force bringing together and dispersing matter but its precise form is unclear as all of Anaximander's work has been lost and is only known through a single sentence and references in later writer's works.
Recent scholarship argues that he, rather than Thales, should be considered the first western philosopher owing to the fact that a direct and undisputed quote from Anaximander exists (even if it is only one sentence) while not even a fragment still exists by Thales. Anaximander invented the idea of models, drew the first map of the world in Greece, and is said to have been the first to write a book of prose.
He traveled extensively and was highly regarded by his contemporaries. Among his major contributions to philosophical thought was the above-mentioned claim that the 'basic stuff' of the universe was the apeiron, a philosophical and theological claim which is still debated among scholars today and which, some argue, provided Plato with the basis for his cosmology.
The Apeiron
Nothing is known of Anaximander's life but his work was considered so significant that it was referenced at length by later writers. The Neo-Platonist philosopher Simplicius (l. c. 490-c.560 CE) writes:
Of those who say that it is one, moving, and infinite, Anaximander, son of Praxiades, a Milesian, the successor and pupil of Thales, said that the principle and element of existing things was the apeiron [indefinite or infinite] being the first to introduce this name of the material principle. He says that it is neither water nor any other of the so-called elements but some other apeiron nature, from which come into being all the heavens and the worlds in them. And the source of coming-to-be for existing things is that into which destruction, too, happens 'according to necessity; for they pay penalty and retribution to each other for their injustice according to the assessment of time,' as he describes it in these rather poetical terms. It is clear that he, seeing the changing of the four elements into each other, thought it right to make none of these the substratum, but something else besides these; and he produces coming-to-be not through the alteration of the element, but by the separation off of the opposites through the eternal motion. (Physics, 24)
This statement by Anaximander regarding elements paying penalty to each other according to the assessment of time is considered the oldest known piece of written Greek philosophy, and its precise meaning continues to be debated. It is thought that the apeiron was envisioned as a creative force, continually bringing matter together, creating new forms, destroying them, and then reforming them again. The significance of the concept is that is clearly suggested a cosmic force but not a divine entity. The apeiron was not a god; it was energy. The formulation of this concept is all the more impressive when one considers it was conceived of at a time when the existence of the Greek anthropmorphic gods was a given. Even Thales' proposal of a First Cause remained close to the accepted paradigm of the creation and operation of the world; Anaximander's departed from that completely.
Thales claimed that the First Cause of all things was water based on his observation that water took on different forms. Whatever the First Cause was, Thales reasoned, had to have attributes of all things which came later. Water was a liquid but, when heated, became air (steam) and, when cooled, became a solid (ice), and could also mix with earth to dissolve it into mud but then harden to agin become a solid. Water, therefore, partook in the qualities of all the four known elements.
Anaximander, however, recognized that water was just another of the earthly elements and suggested no more ancient origin than the other three. He concluded that the First Cause had to come from something beyond the observable world but still able to be apprehended by the operation of that world. His answer to the question of 'Where did everything come from?' was the apeiron, the boundless, but, as noted, what exactly he meant by 'the boundless' has given rise to the centuries-old debate. Does 'the boundless' refer to a spatial or temporal quality or does it refer to something inexhaustible and undefined?
While it is impossible to say with certainty what Anaximander meant, a better understanding can be gained through the so-called 'long since' argument which Aristotle phrases this way in his Physics,
Some make this [First Cause] (namely, that which is additional to the elements) the Boundless, but not air or water, lest the others should be destroyed by one of them, being boundless; for they are opposite to one another (the air, for instance, is cold, the water wet, and the fire hot). If any of them should be boundless, it would long since have destroyed the others; but now there is, they say, something other from which they are all generated. (204b 25-29)
In other words, none of the observable elements could be the First Cause because all observable elements are changeable and, were one to be more powerful than the others, it would have long since eradicated them. As observed, however, the elements of the earth seem to be in balance with each other, none of them holding the upper hand and, therefore, some other source must be looked to for a First Cause. In making this claim, Anaximander becomes the first known philosopher to work in abstract, rather than natural, philosophy and the first metaphysician even before the term 'metaphysics' was coined.
Proto-theory of Evolution & the First Map
In addition to his contributions to metaphysics, Anaximander has also been credited with a proto-theory of evolution as remarked on by later writers:
Anaximander said that the first living creatures were born in moisture, enclosed in thorny barks and that as their age increased they came forth on to the drier part and, when the bark had broken off, they lived a different kind of life for a short time. (Aetius, V, 19)
He says, further, that in the beginning man was born from creatures of a different kind because other creatures are soon self-supporting, but man alone needs prolonged nursing. For this reason he would not have survived if this had been his original form. (Plutarch, 2)
He is also credited with drawing the first map:
Anaximander the Milesian, a disciple of Thales, first dared to draw the inhabited world on a tablet; after him Hecataeus the Milesian, a much travelled man, made the map more accurate, so that it became a source of wonder. (Agathemerus, I, i)
He charted the heavens, traveled widely, was the first to claim that the earth floated in space, and the first to posit an unobservable First Cause. His apeiron is thought to have influenced the Platonic concept of a Realm of Forms, the "true reality", of which the observable world is only a reflection. Whether the apeiron inspired Plato is, like almost everyting else about Anaximander, debated but his concept of the infinite from which all else comes shares a great deal in common with Aristotle's concept of the Prime Mover, that which, unmoving itself, sets everything else in motion.
He is said to have lived to an old age and been widely respected. Diogenes Laertius writes, "Apollodorus, in his Chronicles, states that in the second year of the fifty-eighth Olympiad, [Anaximander] was sixty-four years old. And soon after he died, having flourished much about the same time as Polycrates, the tyrant, of Samos." A statue was erected at Miletus in Anaximander's honor while he lived and his legacy still lives on centuries after his death.
