DATE AND TRADITIONS 
355 
More particulars are, it is true, furnished by Arabian 
authors. We are told that 
‘ Euclid, son of Naucrates, and grandson of Zenarchus [the 
Fihrist has ‘ son of Naucrates, the son of Berenice (?) ’], called 
the author of geometry, a philosopher of somewhat ancient 
date, a Greek by nationality, domiciled at Damascus, born at 
Tyre, most learned in the science of geometry, published 
a most excellent and most useful work entitled the foundation 
or elements of geometry, a subject in which no more general 
treatise existed before among the Greeks : nay, there was no 
one even of later date who did not walk in his footsteps and 
frankly profess his doctrine. Hence also Greek, Roman, 
and Arabian geometers not a few, who undertook the task of 
illustrating this work, published commentaries,. scholia, and 
notes upon it, and made an abridgement of the work itself. 
For this reason the Greek philosophers used to post up on the 
doors of their schools the well-known notice, “Let no one 
come to our school, who has not first learnt the elements 
of Euclid 1 
This shows the usual tendency of the Arabs to romance. 
They were in the habit of recording the names of grand 
fathers, w T hile the Greeks were not ; Damascus and Tyre were 
no doubt brought in to gratify the desire which the Arabians 
always showed to connect famous Greeks in some way or other 
with the east (thus they described Pythagoras as a pupil of the 
wise Salomo, and Hipparchus as ‘ the Chaldaean ’). We recog 
nize the inscription over the doors of the schools of the Greek 
philosophers as a variation of Plato’s yrjSeh dyeoyiirp-qro^ 
eio-LTco] the philosopher has become Greek philosophers in 
general, the school their schools, while geometry has become 
the Elements of Euclid. The Arabs even explained that the 
name of Euclid, which they pronounced variously as Uclides or 
deludes, was compounded of Ucli, a key, and Bis, a measure, or, 
as some say, geometry, so that Uclides is equivalent to the 
key of geometry ! 
In the Middle Ages most translators and editors spoke of 
Euclid as Euclid of Megara, confusing our Euclid with Euclid 
the philosopher, and the contemporary of Plato, who lived about 
400 b. c. The first trace of the confusion appears in Valerius 
1 Casiri, Bibliotheca Arabico-Hispana Escurialensis, i, p. 889 (Casiri’s 
source is the Ta'rtkh al-Hukamd of al-Qiftï (d. 1248). 
A a 2