FUNCTIONAL INERTIA AS LATENT PERIODS, &c. 29 



activity, no activity at any higher potential is per- 

 mitted this is functional inertia. 



A very familiar example will illustrate the limit- 

 setting nature of functional inertia in the organism 

 as a whole. A certain piece of manual labour is to 

 be done : the labourer who is to be paid by time 

 takes, we shall say, eight hours to " the job," works 

 at a low potential and does not get very tired at the 

 end of it ; the same piece of work could be done by 

 an enthusiastic amateur in one-third of the time ; 

 he would exhibit much less inertia, work at a much 

 higher potential and be correspondingly exhausted. 



On the subject of limits Dr. Maudsley writes in the 

 following suggestive way : 



'It is a mistake, however, to say . . . that heat 

 and external conditions determine the rate of growth. 

 The rate of germination, for example, certainly 

 varies according to external conditions, but the 

 limits of variation are fixed by the inherent properties 

 of the structure."* Dr. Maudsley t in this passage 

 means exactly what I do when for "properties" I 

 substitute " the property of functional inertia," &c. 

 ' The seeds of a begonia taken from the same pod 

 will, as Mr. Paget has pointed out, germinate some in 

 a day, some at the end of a year, and some at various 

 intermediate times, even when they are all placed 

 under the same external conditions ; and the same 

 author has pointed out other indications of self- 

 dependent time-rates in the lower organisms. There 



* The italics are mine. 



f H. Maudsley, " Body and Mind," 1870, p. 171. 



