A CONCRETE CASE: SPENCER'S HANDS 201 



that, so far as we can understand, a very complex and special 

 mechanism would be necessary if a modification in, say, the eye 

 is specifically to affect the germinal material. 



Dr. George Ogilvie (1901) writes : "In a subject so involved 

 in obscurity the present incomprehensibility of certain relations 

 can hardly serve as an argument against their existence. The 

 development of the apparently uniform germ-plasm into the 

 infinite differentiation of a complex cell-state is, although no 

 longer a matter of doubt, perhaps not less inconceivable." But 

 this illustration is not altogether appropriate, since our inability 

 to conceive the precise " how " of development rests on our 

 inability to restate in simpler terms any of the fundamental 

 facts of life, such as growth, assimilation, or reproduction, whereas 

 the supposed relation between soma and germ-cells is inconceiv- 

 able in rather a different sense. 



A better illustration, it seems to us, would be found in the 

 difficulty of exactly stating how particular changes in the gonads 

 are correlated with particular changes in the body — e.g. in the 

 changes associated with puberty, conception, ovarian and testi- 

 cular disease. Yet here we can at least imagine what the 

 general nature of the physiological nexus may be — in terms, for 

 instance, of internal secretions or " hormones." 



A Concrete Case : Spencer's Hands. — It may illumine the 

 abstract argument to take a concrete case. Why had Herbert 

 Spencer small hands ? He says that it was because his grand- 

 father and father were schoolmasters, who did little manual 

 work from day to day, save in wielding the pen and sharpening 

 the pencil. Through disuse of the sword and the spade their 

 hands were " directly equilibrated " towards smallness. But 

 since Mr. Spencer senior was " a combination of rhythmically 

 acting parts in moving equilibrium," the dwindling of the hands 

 and the moulding of the physiological units thereof reverberated 

 through the whole aggregate ; a change towards a new state of 

 equilibrium " was propagated throughout the parental system— 



