Mathematical philosophy, a study of fate and freedom; lectures for educated laymen, by Cassius J. Keyser.

THE GROUP CONCEPT 231
idea in the lines just now quoted was ancient two thousand
years before he was born. You should note that the
Spencerian universe of transformations narrowly escapes
being a closed system-escapes by the last six words of
foregoing quotation. The cosmic cycles do indeed follow
each other in an endless sequence-" ever the same in
principle but never the same in concrete result." The
repetitions are such " in principle " only, not in resultthere is always something new.
One of the very greatest works of man is the De Rerum
Natura of Lucretius-immortal exposition of the thought
of Epicurus, " who surpassed in intellect the race of man
and quenched the light of all as the ethereal sun arisen
quenches the stars." Neither a student of philosophy nor
a student of natural science can afford to neglect the reading of that book. For, although it contains many,-very,
very many,-errors of detail,-some of them astonishing
to a modern reader,-yet there are at least four great
respects in which it is unsurpassed among the works that
have come down from what we humans, in our ignorance
of man's real antiquity, have been wont to call the
ancient world: it is unsurpassed, I mean, in scientific
spirit; in the union of that spirit with literary excellence;
in the magnificence of its enterprise; and in its anticipation of concepts among the most fruitful of modern
science. For such as can not read it in the original there
are, happily, two excellent English translations of it-one
by H. A. J. Munro and a later one by Cyril Bailey. Of
this work I hope to speak further in a subsequent lecture
of this course. My purpose in citing it here is to signalize
it as being perhaps the weightiest of all contributions to
what I have called the philosophy of the cosmic year.
The Lucretian universe though not a finite system, is