FALLACIES OF GENERALIZATION. 423 



Polity is an instance of a false analogy from physical 

 bodies to what are called bodies politic. " As there 

 could be in natural bodies no motion of anything 

 unless there were some which moveth all things, and 

 continueth immovable; even so in politic societies 

 there must be some unpunishable, or else no man 

 shall suffer punishment." There is a double fallacy 

 here, for not only the analogy, but the premiss from 

 which it is drawn, is untenable. The notion that there 

 must be something immovable which moves all 

 others, is the old scholastic error of a primum mobile. 



Some of the false analogies upon which systems of 

 physics were confidently grounded in the time of the 

 Greek philosophers, are such as we now call fanciful, 

 not that the resemblances are not often real, but that 

 it is long since any one has been inclined to draw 

 from them the inferences which were then drawn. 

 Such, for instance, are the curious speculations of the 

 Pythagoreans on the subject of numbers. Finding 

 that the distances of the planets bore or seemed to 

 bear to one another a proportion not varying much 

 from that of the divisions of the monochord, they in- 

 ferred from it the existence of an inaudible music, that 

 of the spheres : as if the music of a harp had depended 

 solely on the numerical proportions, and not on the 

 material, nor even on the existence of any material, 

 any strings at all. It has been similarly imagined 

 that certain combinations of numbers, which were 

 found to prevail in some natural phenomena, must 

 run through the whole of nature: as that there must 

 be four elements, because there are four possible com- 

 binations of hot and cold, wet and dry : that there 

 must be seven planets, because there were seven 

 metals, and even because there were seven days of 

 the week. Kepler himself thought that there could 



