of geometry and
arithmetic; and it was probably from his teaching that the Pythagoreans
were led to regard numbers in some mysterious manner as the basis and
essence of all things. He was however more of the religious teacher
than of the philosopher; and he looked upon himself as a being destined
by the gods to reveal to his disciples a new and a purer mode of life.
He founded at Croton in Italy a kind of religious brotherhood, the
members of which were bound together by peculiar rites and observances.
Everything done and taught in the fraternity was kept a profound secret
from all without its pale. It appears that the members had some private
signs, like Freemasons, by which they could recognise each other, even
if they had never met before. His doctrines spread rapidly over Magna
Graecia, and clubs of a similar character were established at Sybaris,
Metapontum, Tarentum, and other cities.

At Athens a new direction was given to the study of philosophy by
Socrates, of whom an account has been already given. To his teaching
either directly of indirectly may be traced the origin of the four
principal Grecian schools: the ACADEMICIANS, established by Plato; the
PERIPATETICS, founded by his pupil Aristotle; the EPICUREANS, so named
from their master Epicurus; and the STOICS, founded by Zeno.

PLATO was born at Athens in 429 B.C., the year in which Pericles died.
His first literary attempts were in poetry; but his attention was soon
turned to philosophy by the teaching of Socrates, whose lectures he
began to frequent at about the age of twenty. From that time till the
death of Socrates he appears to have lived in the closest intimacy with
that philosopher. After that event Plato withdrew to Megara, and
subsequently undertook some extensive travels, in the course of which
he visited Cyrene, Egypt, Sicily, and Magna Graecia. His intercourse
with the elder and the younger Dionysius at Syracuse has been already
related His absence from Athens lasted about twelve years; on his
return, being then upwards of forty, he began to teach in the gymnasium
of the Academy. His doctrines were too recondite for the popular ear,
and his lectures were not very numerously attended. But he had a
narrower circle of devoted admirers and disciples, consisting of about
twenty-eight persons, who met in his private house; over the vestibule
of which was inscribed--"Let no one enter who is ignorant of geometry."
The most distinguished of th