Anaximander of Miletus
611 BC - 547 BC
Greek philosopher and astronomer Anaximander constructed the first precise geometrical model of the universe, which, from one primordial substance, he speculated, arose out the separation of opposite qualities.
He lived in Asia Minor, before Socrates. He belonged to the school and learned the teachings of Thales, his master. He succeeded Thales as the second master of that school and counted Anaximenes and arguably Pythagoras among his pupils.
People today know little of his life and work. According to available historical documents, people know that he wrote down his studies despite only one extant fragment of his work. After his death, fragmentary testimonies, found in documents, provide a portrait of the man.
An early proponent of science, he tried to observe and to explain different aspects with a particular interest in its origins. He claimed that laws rule nature just like human societies, and nothing disturbs its balance and lasts long, Contributions of Anaximander like many thinkers of his time relate to many disciplines. He tried to describe the mechanics of celestial bodies in relation to the Earth. In physics, his postulation of the indefinite source of all things led to a new level of conceptual abstraction. His knowledge allowed him to introduce the gnomon. He created a map that contributed greatly to the advancement of geography of the world. The politics of Miletus also involved him, and people sent him as a leader to its colony.
Anaximander claimed that an "indefinite" principle gives to all natural phenomena. Carl Sagan claims that he conducted the earliest recorded scientific experiment.
“The Earth is cylindrical, three times as wide as it is deep, and only the upper part is inhabited. But this Earth is isolated in space, and the sky is a complete sphere in the center of which is located, unsupported, our cylinder, the Earth, situated at an equal distance from all the points of the sky.”