SECT. III.] INFLUENCE OP SURROUNDING NATURE. 329 



sumption of specific differences. Such an explanation, how- 

 ever, loses its probability when we can show that external con- 

 ditions and historical events possess a more decided influence 

 on the degree of the development of mankind. In order to ar- 

 rive at a true estimate of human nature itself, and the various 

 states of civilization in which we find man, we must first ex- 

 amine what it is that induces him to leave the natural state, 

 what leads him from one step of development to a higher one, 

 and what delays and prevents his mental elevation or renders 

 it stationary. 



These questions are as comprehensive as they are difficult, 

 so that a satisfactory answer can scarcely be hoped for. This 

 consideration does not restrain us from making the attempt, 

 though we are conscious that the results can be but incomplete. 

 Besides, such an investigation however imperfect it may be, 

 deserves some acknowledgment in opposition to the simple 

 declaration that the various degrees of civilization resulted 

 from specific psychical differences, inasmuch as it traces the 

 differences of culture back to certain causes and motives, 

 whilst the assumption of specific psychical differences cuts the 

 matter short ab initio, thus leaving the various phenomena of 

 progressive civilization unexplained. 



The paramount influence which surrounding nature has on 

 the development of the human being, is generally admitted. 

 It is usually the more powerful the nearer a people is to the 

 natural state, and diminishes in influence in proportion as hu- 

 man art and science gain power over it, though even in civi- 

 lized communities, agriculture, industry, or trade, remain per- 

 manently under the influence of the nature of the country. It 

 is evident that the manner in which the above pursuits are 

 followed is one of the most important agents, and gives a 

 national stamp to the mental individuality of a people. 



The first and most important influence which man experiences 

 from surrounding nature is that of its climatic condition. It is 

 not easy correctly to estimate its influence upon mental devel- 

 opment ; for we meet here with the same difficulty, as when we 

 treated of its influence in physical development, inasmuch as it 

 acts in combination with other agents, and we are unable posi- 



