From these examples of speeches it is possible to 

 conclude that in his early years Baer was already an 

 opponent of the collection of facts not illustrated by 

 theoretical generalization. Of the importance for science 

 of both empirical and theoretical investigation and of 

 their relation, Baer wrote in the same article: "There 

 are two ways in which natural science can succeed: observa- 

 tion and meditation. The investigator goes into the majority 

 of cases in one of these ways. Some of them are thirsty for 

 facts, others for results and general laws; some of them 

 for information, others for knowledge; the first can be 

 called the careful investigators and the latter the serious 

 ones. Fortunately, the human mind is rarely developed so 

 one-sidedly that he uses only one way of investigation, 

 disregarding the other. Despised abstraction at the time 

 of his observations involuntarily leads to meditation, and 

 his opponent only in the short period of fever can be 

 engaged in speculations in the sphere of natural science, 

 absolutely disregarding the data of the experiment. For 

 the individual personality, as well as for an entire age 

 of science, one tendency may be predominant and the objec- 

 tives follow it consciously, but the other is not excluded 

 completely. ,?1 



These two sides of scientific investigation — experiment 

 and theoretical discussion, observation and meditation — 

 were always taken into consideration by Baer, and he put 

 them in the form of a subtitle sounding like an epigraph to 

 his great work: (JBER ENTWICKLUNGSGESCHICHTE DER THIERE: 

 BEOBACHTUNG UND REFLEXTION. It is not by chance, however, 

 that here, as in other cases, observation is put before 

 meditation. One can reflect only upon what has already been 

 observed; Baer did not recognize any a priori truths. 11 



"Investigation of nature," Baer wrote, "in general must 

 start from the observation of individual phenomena, and the 

 latter only in that extent are combined into a universal 

 authenticity, as far as this allows. There also, where it 



10. Ibid. , p. 31. 



11. In this idea he made an exception only for mathematics 



494 



