28 MODES OF RESEARCH IN GENETICS 



One cannot escape the feeling that the statistical 

 ratios themselves, derived from experiment and 

 capable of direct verification, are the only really 

 definite and substantial things in the case. The 

 reduplication theory, in spite of the fact that it 

 is stated in cytological terms, appears logically 

 to be purely a statistical hypothesis for the gradua- 

 tion of a particular kind of observational data. 

 Logically it falls in the same category of operations 

 as fitting a curve to a series of physical observa- 

 tions. To this no objection can be raised. The 

 only point is that any one who has had experience 

 in the mathematics and logic of graduating ob- 

 servational data will not be inclined to rate 

 the evidence in support of the qualitative cytologi- 

 cal aspects of the hypothesis at quite so high a 

 value as might seem at first thought to be war- 

 ranted. 



The logic of the case is possibly worth going into 

 a little farther, since it involves what seems to 

 me to be one of the most insidious and prevalent 

 fallacies in biological research. ^ An investigator 

 discovers some new and curious facts, which are 

 capable of numerical expression. He then frames 

 an hypothesis to account for them. Depending 



^ One wonders how prevalent the same fallacy may be in other 

 sciences. The writer does not have an intimate enough familiarity 

 with the actual facts to form anything more than a suspicion. The 

 suspicion is, however, that it will not become either the physicist or 

 the chemist to assume airs of superiority over the biologist on this 

 point. 



