i.i ORTHOGENESIS 73 



mean here? Without undertaking an exhaustive analysis 

 of the idea of causality, we will merely remark that three 

 very different meanings of this term are commonly con- 

 fused. A cause may act by impelling, releasing, or un- 

 winding. The billiard-ball, that strikes another, deter- 

 mines its movement by impelling. The spark that explodes 

 the powder acts by releasing. The gradual relaxing of 

 the spring, that makes the phonograph turn, unwinds the 

 melody inscribed on the cylinder: if the melody which is 

 played be the effect, and the relaxing of the spring the 

 cause, we must say that the cause acts by unwinding. 

 What distinguishes these three cases from each other is 

 the greater or less solidarity between the cause and the effect. 

 In the first, the quantity and quality of the effect vary 

 with the quantity and quality of the cause. In the second, 

 neither quality nor quantity of the effect varies with quality 

 and quantity of the cause: the effect is invariable. In 

 the third, the quantity of the effect depends on the quantity 

 of the cause, but the cause does not influence the quality of 

 the effect: the longer the cylinder turns by the action 

 of the spring, the more of the melody I shall hear, but the 

 nature of the melody, or of the part heard, does not depend 

 on the action of the spring. Only in the first case, really, 

 does cause explain effect; in the others the effect is more 

 or less given in advance, and the antecedent invoked is — 

 in different degrees, of course — its occasion rather than 

 its cause. Now, in saying that the saltness of the water 

 is the cause of the transformations of Artemia, or that the 

 degree of temperature determines the color and marks 

 of the wings which a certain chrysalis will assume on be- 

 coming a butterfly, is the word "cause" used in the first 

 sense? Obviously not : causality has here an intermediary 

 sense between those of unwinding and releasing. Such, 

 indeed, seems to be Eimer's own meaning when he speaks 



