Greek Mathematics - Thales

Greek Civilization has its roots as old as 2800 BC but The Greek Mathematical era originated from the 6th century BC to the 5th century AD. Even the word mathematics comes from the Greek word “mathema” meaning "subject of instruction”.   

Of course Greeks borrowed lot of knowledge from Egyptian and Babylonians, still their progress in their own civilization and culture is most impressive and influential as compared to previous civilizations. There is no match to the Greeks’ contribution in the field of mathematics. Anything we do in mathematics today, still have its roots in Greek Mathematics directly or indirectly. 

First time in the history of mathematics the personal names evolved. To study about the Greek’s contribution to Mathematics, we can divide the timeline into two periods.

1. Classical period from about 600 BCE to 300 BCE (Thales, Pythagoras, Democritus ,Plato, Aristotle, Hippocrates) 
2. The Alexandrian or Hellenistic period from 300 BCE to 300 A.D. (Euclid and Archimedes)  

There is so much given to mathematics by Greeks that we have to study their contribution in parts. Today we will talk about the classical period for Greek Mathematics and Mathematicians. We will talk about the first Greek name recognized as a mathematician and philosopher, Thales.

Thales born in about 624 BC in Miletus, Asia Minor (now Turkey). He was first ever person recognized as a philosopher, scientist and mathematician. First Greek Mathematician who took scientific approach towards mathematics. He studied in Egypt and improved the Egyptian mathematics a lot and brought this knowledge to Greece. Not much of proof exists for his accomplishments, though he is credited for the five basic geometrical theorems.

Being asked what was very difficult, he answered, in a famous aphorism, “To Know Thyself.” Asked what was very easy, he answered, “To give advice.” To the question, what/who is God?, he answered, “That which has no beginning or no end.” (The infinite!?!) Asked how men might live most virtuously, he answered, “If we never do ourselves what we blame in others.”   He believed in flat Earth. 

Evidence exists that he wrote treatises on geography, astronomy, and cosmology that survived for several centuries. Thales is credited for the following five basic theorems in geometry ;

1. A circle is bisected by any diameter.
2. The base angles of an isosceles triangle are equal.
3. The angles between two intersecting straight lines are equal.
4. Two triangles are congruent if they have two angles and the included side equal. 
5. An angle in a semicircle is a right angle.

Following wikipedia page contains in depth knowledge about Thale

Thale - A Great Mathematician

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