GREATER PROBLEMS OF BIOLOGY—THOMPSON. 383 
which entelechy has formed, are no other than the afo@yre«, whereby 
animalia vivunt et sentiunt, and the dcavontex), to which Aristotle 
ascribes the reasoning faculty of man. Save only that Driesch, like 
Darwin, would deny the restriction of voic, or reasoning, to man alone, 
and would extend it to animals, it is clear, and Driesch himself admits 
that he accepts both the vitalism and the analysis of vitalism laid 
down by Aristotle. 
The zvedya of Galen, the vis plastica, the vis vite formatrix, of the 
older physiologists, the Bildungstrieb of Blumenbach, the Lebenskraft 
of Paracelsus, Stahl, and Treviranus, ‘‘shaping the physical forces of 
the body to its own ends,” “‘dreaming dimly in the grain of the prom- 
ise of the full corn in the ear’’? (to borrow the rendering of an Oxford 
scholar), these and many more, like Driesch’s “‘Entelechy” of to-day, 
are all conceptions under which successive generations strive to depict 
the something that separates the earthy from the living, the living 
from the dead. And John Hunter described his conception of it in 
words not very different from Driesch’s, when he said that his principle, 
or agent, was independent of organization, which yet it animates, 
sustains, and repairs; it was the same as Johannes Miiller’s conception 
of-an innate ‘“‘unconscious idea.” 
Even in the Middle Ages, long before Descartes, we can trace, if we 
interpret the language and the spirit of the time, an antithesis that, 
if not identical, is at least parallel to our alternative between vitalistic 
and mechanical hypotheses. For instance, Father Harper tells us 
that Suarez maintained that in generation and development a divine 
interference is postulated, by reason of the perfection of living beings; 
in opposition to St. Thomas, who (while invariably making an excep- 
tion in the case of the human soul) urged that, since the existence of 
bodily and natural forms consists solely in their union with matter, 
the ordinary agencies which operate on matter sufficiently account 
for them.° 
But in the history of modern science, or of modern physiology, it 
is, of course, to Descartes that we trace the origin of our mechanical 
hypotheses—to Descartes, who, imitating Archimedes, said: “‘Give 
me matter and motion and I will construct the universe.” In fact, 
leaving the more shadowy past alone, we may say that it is since 
Descartes watched the fountains in the garden and saw the likeness 
1 Science and Philosophy of the Organism (Gifford Lectures), ii. p. 83, 1908. 
2 Cit. Jenkinson (Art. ‘‘ Vitalism” in Hibbert Journal, April, 1911), who has given me the following quota- 
tion: ‘Das Weitzenkorn hat allerdings Bewusstsein dessen was in ihm ist und ausihm werden kann, und 
traiimt wirklich davon. Sein Bewusstsein und seine Traitime mégen dunkel genug sein”; Treviranus, 
Erscheinungen und Gesetze des organischen Lebens, 1831. 
3 “Cum formarum naturalium et corporalium esse non consistat nisi in unione ad materiam, ejusdam 
agentis esse videtur eas producere, cujus est materiam transmutare. Secundo, quia cum hujusmodi form 
non excedant virtutem et ordinem et facultatem principiorum agentium in natura, nulla videtur necessitas 
eorum originemin principia reducere altiora.” Aquinas, De Pot. Q., iii.a ll. Cf, Harper, Metaphysics of 
the School. iii. 1. p. 152. 
