26 JDABWINISM TESTED BY 



conclusions arrived at through that channel. 

 All a priori fabrics, all cut-and-dry sj'^stems, 

 are not entitled to any higher consideration 

 than any other witty trifling ; their place is 

 in the lumber-room of science. 



Now observation teaches us that all living 

 organisms, which fall at all within the 

 proper reach of our observation, vary accord- 

 ing to definite laws. These changes or varie- 

 ties, this life, is the real essence or being of 

 any organism ; and we never know anj^thing 

 about the latter until we are cognizant of 

 the former in their undivided entirety. In 

 other words, so long as we are ignorant of 

 how a thing arose we cannot be said to 

 know it. The great importance which the 

 developmental history and the scientific 

 cognition of the life of the different organisms 

 has assumed for the natural science of our 

 time, is the necessary result of the principle 

 of observation. 



