Euclid

Euclid  (fl. 300 BC), a Greek mathematician, is known as the Father of Geometry. His work Elements served as the primary geometry textbook until the early 20th century. In addition to geometry, Euclid also pioneered what we think of as number theory. 
For more information, see the following: 
*http://www.britannica.com/EBchecked/topic/194880/Euclid
*http://www-groups.dcs.st-and.ac.uk/~history/Biographies/Euclid.html
*http://aleph0.clarku.edu/~djoyce/java/elements/elements.html
=="The Common Life" ==
Euclid appears in Stevens' poem "The Common Life" that appeared in the collection Parts of a World: 
 That's the down-town frieze,
 
 Principally the church steeple, 
 
 A black line beside a white line;
 
 And the stack of the electric plant, 
 
 A black line drawn on flat air. 
 
 
 It is a morbid light 
 
 In which they stand, 
 
 Like an electric lamp 
 
 On a page of Euclid. 
 
 
 In this light a man is a result,
 
 A demonstration, and a woman, 
 
 Without rose and without violet, 
 
 The shadows that are absent from Euclid, 
 
 Is not a woman for a man. [1]
==References ==
1. Wallace Stevens, Collected Poetry and Prose, Library of America 1997. Page 204.