1256
While flawed , this became the fundamental basis on which later Greek philosophers and mathematicians like Euclid would construct some of the most important theories of light , vision , and optics .
 person: Euclid
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities: Euclid 
Answer:
 person: Euclid