PRESIDENTS ADDRESS—SECTION A. 21 
called modern doctrine of the conservation of mass, viz., that 
“out of nothing arises nothing; nothing that exists can be 
destroyed ; all change consists in the combination and separa- 
tion of atoms” (7). 
7. Epicurus’ Theory.—The physics of Epicurus (0) was based 
wholly on the doctrines of Democritus, and helped to establish 
this conception as a permanent element of human thought, not, 
perhaps, so much directly and during his, Epicurus’, life—though 
even then he made many disciples, and was widely known—as 
indirectly, and long afterward, through the agency of his 
admirer, Lucretius (p). According to Epicurus, the number of 
bodies in the universe is limitless, since it is unbounded ; atoms 
are, and from all eternity have been, in constant motion; they 
have no qualities, excepting size, figure, and weight; in respect 
of the first they are to be regarded as immeasurably small; in 
respect of figure the variety is inconceivably great, but ‘not 
actually infinite, though in a finite body both the number and 
variety are limited, and hence there is no such thing as infinite 
divisibility. (q¢). 
8. Lucretius and his Poem.—It would be difficult to form any 
opinion as to how far the doctrine of Epicurus would have made 
its way in human thought, had it not been for the ardent appre- 
ciation of Lucretius, not only in respect of the doctrine itself, 
but also in respect of what he conceived to be its religious or 
philosophical import (r). There can be no doubt, however, that 
it is to Lucretius’ great poem, “ De Rerum Natura,” and to its 
wide contact with educated humanity, that the world owes its 
deep tincture of atomism. 
Agreeing generally with the views of Democritus and Epicurus, 
Lucretius qualified, however, the idea that atoms are of indefi- 
nitely great variety. His argument that the number is finite 
conveys also the impression that it is by no means great. The 
atoms, impenetrable, indivisible though having parts or exten- 
sion in space, indestructible, “strong and eternal in their solid 
singleness” (s), he supposed to vary in form, size, and weight, 
as also did Epicurus; but Lucretius is more explicit as to the 
question of form. Epicurus had written on the angle of the 
(xn) Zeller. Op. cit. I.,691. Anm, 2. 
(0) [842—270 B.C.] 
(p) [99—55 B.C.]. 
(g) See Lange. Geschichte des Materialismus. I..1V., pp.104—105. Eng. Trans 
(rv) Epicurus’ courage in promoting a non-theistic v iew of the creation of the universe 
seems to have aroused nothing short of passionate admiration on the part of Lucretius, 
as the memorable sentence following on the introduction to Memmius abundantly 
shows :—‘‘ When human life lay shamefully prostrate on earth, crushed down under the 
weight of Religion, who showed her face from heaven, with hideous aspect frowning upon 
mortals, a man of Greece first ventured to lift his mortal eyes to her face, first ventured 
to withstand her openiy. Him neither stories of the gods, nor thunderbolts, nor heaven’s 
threatening roar could make afraid, but rather enhanced the eager courage of his soul in 
its desire to first burst the bars of Nature’s portals.’’ 
(s) Solida pollentia simplicitate. I.. 574. 
Aeterna pollentia simplicitate. I., 612. 
