24 PRESIDENTS ADDRESS— SECTION A. 
an effect. Gassendi’s claim to recognition in connection with 
the development of the atomistic view depends, not upon any 
contribution he directly made, but upon his espousal and ex- 
position thereof at a time when the scholastic views were rife ; 
it was then a bold thing to challenge Aristotle. 
12. Boyles Application of Atomism.—Gassendi greatly in- 
fluenced his contemporaries, Boyle (a) and Newton (6), the 
former acknowledging in an especial way his indebtedness to 
Gassendi’s small, but valuable, compendium of the philosophy of 
Epicurus, whose views he (Boyle) regretted he had not earlier 
adopted (c). As Gmelin (d) and Kopp (e) fully recognise, Boyle 
is a critical figure in the history of modern physical science. 
Not only did his “ Chemista Scepticus (f) give a death-blow to 
alchemy and incidentally to Aristotelian physics, but he was, if 
not the first, one of the first among modern physicists who 
realised the importance of well-designed and accurately-con- 
structed apparatus in physical investigations ; he, moreover, con- 
ceived the problem of the chemical elements in substantially the 
same form as it is now presented (g). Boyle regarded the 
atomic conception as explanatory of qualitative differences in 
matter (7). 
13. Descartes—From one point of view Descartes’ (7) influence 
on the atomic theory appears small in respect of its fundamental 
conceptions ; to some extent, he may even be cited in opposition 
to it, more particularly to the form it had in the mind of 
Lucretius and his predecessors. Nevertheless, the stress he laid 
on the mechanical interpretation of natural phenomena, and the 
value of his co-ordinate geometry in that respect, connects him 
with important aspects of the theory. Descartes’ doctrine ()), 
published in 1644, is that :—(a) Extension alone constitutes the 
essential nature of matter (sec. 4, p. 25); (6) there is no such 
thing as a void or empty space in the sense understood by philo- 
sophers (sec. 16, p. 30); (c) and, similarly and strictly speaking, 
there are no atoms, if atoms are to be regarded as small indi- 
visible bodies (sec. 20, p. 31); (d) the universe is indefinitely 
extended (sec. 21, p. 31); (e) matter is essentially the same 
throughout it (sec. 22, p. 32); (f) that all its varieties of form, 
and the properties that appertain to those varieties, are depen- 
dent upon the motions of part of this plenum (sec. 23, p. 32); 
(a) [1627—1691]. 
(b) [1642—1797]. 
(6) Origin of Forms and Qualities according to the Corpuscular Philosophy. Oxford, 
664. 
(dz) Gesch. der Chemie. Gdott., 1798. II., 35. Gmelin observes that no man con- 
tributed so largely to destroy the authority which Alchemy had exerted over so many 
minds and sciences. 
(e) Gesch.d. Chemie. I., 163 ff. 
(f) 1661 or 1662? 
(4) eee Op. cit. I1., 224 ff. 
(h) Op. 
(i) [15961650]. 
(7) Opera Philosophica. Renati Descartes Amstelod. 1677. Pars sec. 
