THE WONDERS OF LIFE 



with the acuteness and clearness of his vision. Fre- 

 quently the means has been turned into the end of 

 knowledge. In the reproduction of the thing observed 

 the objective photograph, presenting all parts of the 

 object with equal plainness, has been more valued than 

 the subjective design that reproduces only what is 

 essential and leaves out what is superfluous; yet the 

 latter is in many cases (for instance, in histological 

 observation) much more important and correct than 

 the former. But the greatest fault has been that many 

 of these "exact" observers have refrained altogether 

 from reflection and judgment on the phenomena ob- 

 served, and have neglected subjective criticism; hence 

 it is that so often a number of observers of the same 

 phenomenon contradict each other, while each one 

 boasts of the "exactness" of his observations. 



Like observation, experimentation has been wonder- 

 fully improved of late years. The experimental sciences 

 which make most use of it — experimental physics, 

 chemistry, physiology, pathology, etc. — have made as- 

 tounding progress. But it is just as important in the 

 case of experiment — or observation under artificial con- 

 ditions — as of simple observation that it be undertaken 

 and carried out with a sound and clear judgment. 

 Nature can only give a correct and unambiguous answer 

 to the question you put her when it is clearly and dis- 

 tinctly proposed. This is very often not the case, and 

 the experimenter loses himself in meaningless efforts, 

 with the foolish hope that "something may come of 

 it." The modern province of experimental or me- 

 chanical embryology is especially marred by these use- 

 less and perverse experiments. Equally foolish is the 

 conduct of those biologists who would transfer the ex- 

 periment that is valuable in physiology to the field of 

 anatomy, where it is rarely profitable. In the modern 

 controversy about evolution the attempt is frequently 



8 



