GEOGRAPHER, PHYSICIST

Life
One of the great ancient philosophers, Anaximander studied with Thales of Miletus and taught Anaximenes. Very little is known of his life, beyond the fact that he came from a prominent Milesian family, that his father's name was Praxiades, and that he took an active part in the political life of the city. He made a number of inventions, wrote treatises on geography, astronomy, mathematics and cosmography, and was the first philosopher to break with tradition by writing in prose rather than in verse.


Work
Anaximander is held to be the founder of scientific geography, for he was the first to draw a map of the entire known world (550 BC). This work was not designed to serve any practical purpose, but was purely an attempt to reduce to order the geographical facts known to his age. His map was spherical, because that was how he conceived the Earth to be: a sphere floating freely centre of the heavens.

Anaximander invented the solar gnomon, or "sciotheres" (= shadow-chaser), an instrument, which could be used to determine midday, the points of the compass, the solstices and the equinoxes. It could also be used to calculate the length of a day, the number of hours, and the exact time of day. The gnomon thus proved to be an extremely useful instrument for measuring time, and became the basis for the development of sundials, out of which in turn were developed a number of astronomical instruments as well as the portable sundials that were the precursors of our modern clocks and watches.

Perhaps his most important discovery was the revolution of celestial bodies. He also formulated the theory that the heavens are a perfect sphere and that the Earth, rather than being supported in some manner (as it was earlier thought), floats freely at its centre. He was the first to try to determine the magnitude of the celestial bodies, the distances between them, and how they are positioned in space.

Anaximander thought that all the celestial bodies, and therefore the Earth as well, had their origin in what he called the "apeiron", a primal unity of unbounded matter. (This was a rejection of Thales' theory that water was the primary substance.) He accepted a certain primal differentiation into contrasting qualities, namely cold (air) and hot (fire), an opposition, which subsequently generated a second, between dry and wet, which eventually produced the dry land and the seas. This fundamental conception underlies his explanation of the creation of the universe.

The very first organisms, he claimed, developed in the mud of seas which had dried out under the action of the sun's rays; their skin was covered with spines, which they gradually lost as they continued to live on dry land, under the influence of the sun. Man, he thought, was surely born from other animals, because, while animals could find what they needed for their survival on their own, man by contrast required a long apprenticeship. In that primeval world, therefore, man could not have survived if he had been created and existed in his modern form.

With his philosophical view of the world and his conception of the shape of the earth "drawn on a tablet", Anaximander laid the foundations for scientific cartography, not merely for Greece but universally. Although the potential germ of his achievements may be identified in older civilisations, particularly the Chaldaean, Anaximander was the first to fix the bounds of the known world and to record them in material form (e.g., on a tablet of wood). His map may not have been accurate; but it was the cornerstone for the sciences of geography, cartography and astronomy, which in the years to follow yielded such brilliant achievements in the exploration and interpretation of the world we live in.

Anaximander's principal writings are:

"On Nature", "On the Fixed Stars", "Geometric Surveying", "Sphere", "Map of Greece" and "Map of the World".