some speculations concerning regulations 463 



§ 169. Spencer's views 



A chief difference between what has been hypothesized in the 

 past and what has been induced here with regard to regulations, 

 may be stated as a contrast between the study of forces and the 

 study of rates. Noting the difficulty of measuring the forces con- 

 cerned in compensatory exchanges, I ascertained the rates con- 

 cerned in them. Actually, speculations in the past about adjust- 

 ments and recoveries have to do with forces, both specifically and 

 generally. To illustrate, I quote the relevant view of Herbert 

 Spencer (1867, pp. 435, 462, 386) : 



This equilibration between the functions of an organism and the actions in its 

 environment, may be either direct or indirect. The new incident force may either imme- 

 diately call forth some counteracting force, and its concomitant structural change; or 

 it may be eventually balanced by some otherwise produced change of function and struc- 

 ture. . . . Direct equilibration is that process currently known as adaptation. . . . Here 

 we further find, that this limit towards which any such organic change advances, in the 

 species as in the individual, is a new moving equilibrium adjusted to the new arrangement 

 of external forces. . . . The only new incident forces which can work the changes of 

 function and structure required to bring any animal or plant into equilibrium with them, 

 are such incident forces as operate on this animal or plant, either continuously or fre- 

 quently. They must be capable of appreciably changing that set of complex rhythmical 

 actions and reactions constituting the life of the organism; and yet must not usually 

 produce perturbations that are fatal. 



Life itself is the maintenance of a moving equilibrium between inner and outer 

 actions — the continuous adjustment of internal relations to external relations; or the 

 maintenance of a correspondence between the forces to which an organism is subject and 

 the forces which it evolves. For if the preservation of life is the preservation of such a 

 moving equilibrium, it becomes a corollary that these changes which enable a species to 

 live under altered conditions, are changes towards equilibrium with the altered conditions. 



Eaising a limb causes a simultaneous shifting of the centre of gravity, and such 

 altered tensions and pressures throughout the body as re-adjust the disturbed balance. 

 Passage of liquid into or out of a tissue, implies some excess of force in one direction 

 there at work ; and ceases only when the force so diminishes or the counter-forces so 

 increase that the excess disappears. A nervous discharge is reflected and re-reflected from 

 part to part, until it has all been used up in the re-arrangements produced— equilibrated 

 by the reactions called out. 



Spencer thus specifies that forces become operative in each 

 equilibration ; and that two sorts of equilibration, direct and indi- 

 rect, may be distinguished. Direct is what is usually meant by 

 biological adaptation. Adaptation is variation in a feature or 

 property of an organism in relation with its state or with the 

 environment ; certainly both forces and exchanges fall under that 

 denomination. In state G the organism has properties gi, 92, etc. ; 

 in state E it has properties h^, Jh, etc. which are more advantageous 



