Theaetetus (mathematician)
Overview
Athens
Athens , is the capital and largest city of Greece. Athens dominates the Attica region and is one of the world's oldest cities, as its recorded history spans around 3,400 years. Classical Athens was a powerful city-state...
, possibly son of Euphronius, of the Athenian deme
Deme
In Ancient Greece, a deme or demos was a subdivision of Attica, the region of Greece surrounding Athens. Demes as simple subdivisions of land in the countryside seem to have existed in the 6th century BC and earlier, but did not acquire particular significance until the reforms of Cleisthenes in...
Sunium, was a classical Greek
Greece
Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....
mathematician. His principal contributions were on irrational
Irrational number
In mathematics, an irrational number is any real number that cannot be expressed as a ratio a/b, where a and b are integers, with b non-zero, and is therefore not a rational number....
lengths, which was included in Book X of Euclid's Elements
Euclid's Elements
Euclid's Elements is a mathematical and geometric treatise consisting of 13 books written by the Greek mathematician Euclid in Alexandria c. 300 BC. It is a collection of definitions, postulates , propositions , and mathematical proofs of the propositions...
, and proving that there are precisely five regular convex polyhedra
Platonic solid
In geometry, a Platonic solid is a convex polyhedron that is regular, in the sense of a regular polygon. Specifically, the faces of a Platonic solid are congruent regular polygons, with the same number of faces meeting at each vertex; thus, all its edges are congruent, as are its vertices and...
.
Theaetetus, like Plato
Plato
Plato , was a Classical Greek philosopher, mathematician, student of Socrates, writer of philosophical dialogues, and founder of the Academy in Athens, the first institution of higher learning in the Western world. Along with his mentor, Socrates, and his student, Aristotle, Plato helped to lay the...
, was a student of the Greek mathematician Theodorus of Cyrene
Theodorus of Cyrene
Theodorus of Cyrene was a Greek mathematician of the 5th century BC. The only first-hand accounts of him that we have are in two of Plato's dialogues: the Theaetetus and the Sophist...
. Cyrene was a prosperous Greek colony on the coast of North Africa, in what is now Libya, on the eastern end of the gulf of Sidra.
Discussions
