Child, Driesch's harmonic equipoteDtial systems in form -regulation. ()13 



monic equipotential systems? If the earlier definitions are correct 

 Tubularia is certainly not a harmonic equipotential system; if these 

 new definitions are correct then all that Driesch has said con- 

 cerning the importance of proportionality in these systems is value- 

 less. For example, the formula x = gA, which Driesch regards 

 as the expression „für das eigentlich Lebensautonome" in locali- 

 zation with decrease of size in Tubularia (Driesch, 1901, pp. 174 — 180; 

 also p. 583 above) can be obtained only by assuming mathemati- 

 cally exact proportionality in Tubularia. If Driesch believes that 

 „nur ganz unbestimmt und allgemein hat unter solchen Umständen 

 das Wort „proportional" einen Sinn" what possible significance 

 can a formula derived from the assumption of mathematically exact 

 proportionality posses for Tubularia? If the formula has no signi- 

 ficance then it is impossible to determine that the „Entelechie- 

 konstante A" exists in the case of Tubularia: or in other words, 

 it is impossible to discover „das eigentlich Lebensautonome" in 

 the phenomena of regulation with decrease of size in this species. 



Actually then, the differences in Driesch's different definitions 

 of the harmonic equipotential system leave us in a dilemma as to 

 what such a system actually is. Furthermore, if typical regional, 

 polar and dimensional differences in localization occur, as they do 

 in Tubularia, they must be the result of some physiological factor 

 or factors existing at the different regions or poles, i. e., of an 

 „extensive Mannigfaltigkeit" or a „machine" in Driesch's sense 

 and cannot be due to the „intensive Mannigfaltigkeit" or „ente- 

 lechie". If, notwithstanding these differences, Tubularia is still a 

 harmonic equipotential system, then it is impossible to obtain evi- 

 dence from it or from any other such system in which such regional 

 or polar or dimensional differences appear, for the hypothesis of 

 „Lebensautonomie". 



In short, if exact proportionality is an essential characteristic 

 of a harmonic equipotential system, Tubularia is not such a system, 

 and if proportionality is not essential then the entelechy-constant 

 cannot be derived from the phenomena of regulation in such systems, 

 since the derivation of this constant assumes exact proportionality. 



V. Fact and regards hypothesis in certain special cases. 



As regards another so-called harmonic equipotential system, 

 viz. the sea-urchin egg^) Driesch himself (Driesch, 1900, 1902 b) 



2) I am glad to acknowledge an error of statement contained in the words; 

 „others have shown that the eggs of the sea-urchin and the ascidian are not har- 

 monic equipotential systems as Driesch supposed them to be" (Child, 1907e, 

 p. 145). This statement is of course entirely incorrect so far as it concerns the 

 sea-urchin egg, as Driesch has pointed out (Driesch, 1998, p. 409). As regards 

 the ascidian egg it is not incorrect, though I should have mentioned the fact that 



