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Important Mathematicians

Then and Now

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Sample Presentation

By

Mrs. Brewster

T H A L E S OF M I L E T U S

Clipart Credit: Thales. Encyclopedia Phoeniciiana

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Lived about 624 BC to 546 BC in Miletus, Asia Minor (now Turkey)  

The first known Greek philosopher, scientist and mathematician.

The only Mathematician in The Seven Wise men of Antiquity.

Introduced Geometry into Greece, after visiting Egypt.

2,000BC 1,000BC 0 1,000AD 2,000AD

THALES

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Contemporaries

Pythagoras

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Accomplishments in Mathematics

•Credited with five theorems of elementary geometry:

Proposition. A circle is bisected by any diameter.

Proposition. The base angles of an isosceles triangle are equal.

Proposition. The angles between two intersecting straight lines are equal.

Proposition. Two triangles are congruent if they have two angles and the included side equal.

Proposition. An angle in a semicircle is a right angle.

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He calculated the size of the great pyramid, for the Egyptians, by using similar triangles.

Pythagoras was his most famous student.

More Accomplishments in Mathematics

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Other Accomplishments•He is said to have predicted an eclipse of the Sun on May 28, 585 BC, startling all of Ionia.

•Thales is also said to have discovered a method of measuring the distance to a ship at sea.

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Quotes Answers Given by Thales

Thales answered, in a famous witty saying, "To Know Thyself."

He answered, "To give advice."

He answered, "That which has no beginning or no end."

(The infinite!!)

What is very difficult?

What is very easy?

What/who is God?

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Anecdote:Aristotle relates a story of how

Thales used his skills to deduce that the next season's olive crop would be a very large one. He therefore bought all the olive presses and then was able to

make a fortune when the bumper olive crop did indeed

arrive.

Anecdote Credit: http://phoenicia.org/thales.html

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Implications for Today

Thales thought up many ideas which are used by people today, such as indirect measurement, and the idea of Infinity.

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Conclusion.Reflections about Thales:

Thales was a revolutionary thinker who impressed his contemporaries by being able to calculate the height of the Great Pyramid of Egypt.

Philosophy, Science and Mathematics were more important to Thales than family or wealth.

He is the first recorded person who tried to explain phenomena, like earthquakes, by rational rather than by supernatural means.

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Annotated ReferencesThales of Miletus http://www.math.tamu.edu/~don.allen/history/thales2/thales2.html ,

Highlights of the life of Thales.

Encyclopedia Phoeniciiana Thales of Miletus http://phoenicia.org/thales.html

Conflicting stories about Thales.

Thales Of Miletus 600 B.C.

http://www.mvrhs.org/netsite/school/departments/Math/Jen's%20folder/thales_of_miletus.htm

A Student’s biography of Thales.

Discovering Geometry Second Ed., Serra, M., Key Curriculum Press, 1997, page 718

Our Textbook

Clipart Credit: google.com

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