Philosophy of Botany. 287 



consequently advances the sciences; idealism, philosophy, re- 

 ligion, history. In the logical procedure realism proceeds in- 

 ductively ; idealism, deductively. 



Never v^'as, in a short interval of time, this division of psychic 

 energy more clearly defined than in the teachings of Plato and 

 Aristotle — men of such eminent wisdom that their axioms 

 rema!ined as guiding stars for these two factions of philosophy 

 for twenty centuries. 



It seems to fit the occasion to explain the principal atti- 

 tudes of mind, instinct and intelligence. 



In his work on " Origin of Species," Darwin gives the fol- 

 lowing definition of instinct : "An action which we ourselves 

 should require experience to enable us to perform, when per- 

 formed by an animal, more especially very yoting ones, without 

 any experience, and when performed by many individuals in 

 the same way, without knowing for what purpose it is per- 

 formed, is usually said to be instinctive. As all instincts show 

 a trace of selective qualities, a trace of reasoning power has also ' 

 to be conceded, even to the lowest ones." He further qualified 

 this tenet by the following doctrines : 



1. The instincts of the species differ with individuals, and 

 are in the same way subject to variation as are the morpho- 

 logical marks of bodily formation. 



2. These variations are by inheritance in part transferred to 

 the descendants, and in the succession of generatioils accumu- 

 lated and confirmed. 



3. Selection (artificial as well as natural) exercises amongst 

 these hereditary variations of vital activities a preference in 

 continuing the most useful and abandoning the less suitable, 

 modifications. 



4. The divergence of physical characters, thus originated, 

 leads to the continuity of succession in the same manner to the 

 origin of new instincts as does the divergence of morpholog- 

 ical' characters produce new species. 



The scholastic mediaeval psychologic views — which even yet 

 have adherents — made an absolute distinction between the 

 psychical activity of animals and man, calling the former " in- 

 stinct " (implanted) and the latter " reason," judging that, ac- 

 cording to the Mosaic histor}- of creation, every species of ani- 



