202 BAIN'S SPONTANEITY 



classical work on the " Senses and Intellect." At p. 64, et seq., 

 he maintains, contrary to Fletcher, that a spontaneous Energy 

 resides in the nerve centres which gives them the power of 

 initiating molecular novements "without any antecedent 

 sensation from without, or emotion from within, or any ante- 

 cedent state of feeling whatsoever, or any stimulus extraneous 

 to the moving apparatus itself." And this " fact of spontaneous 

 activity I look upon as an essential prelude to voluntary 

 power" (296). His chief proofs of this are the tonicity of the 

 muscles ; and to the objection that cutting the sensory roots 

 destroys the tonicity, he says, granting that it is really reflex 

 and arising from perennial irritation of the incarrying fibres, 

 that it is not what we usually understand by stimulation. This 

 last he wishes to restrict to the effect of " visible and remitted 

 applications to the parts. A constant stimulus is no stimulus 

 at all " (64). This may, to a certain extent, apply to conscious 

 sensation where relativity plays an important part, but it is 

 quite inapplicable to mere irritation ; and the permanent action 

 of stimuli, such as heat for example, is essential to continuance 

 of vital activity. Nor would the teleological reason for the 

 stimuli be satisfied by a mere initiatory impulse which will 

 allow action to continue spontaneously till the whole is con- 

 sumed, as in firing gunpowder for example. On the contrary, 

 it must be, and is in most cases, a continued impulse under 

 which the vital activity only takes place as long as it lasts. 

 His other proofs are the contraction of the sphincters and of 

 the capillaries, the rotatory movements produced by uni-lateral 

 section of the pons varolii, the activity of the involuntary 

 movements, the initial beat of the heart, &c., all of which may 

 be easily answered in the same way. But his final and, he 

 thinks, most conclusive proof, is the priority of movement to 

 sensation in wakening from sleep, a circumstance noticed by 

 Aristotle, who referred these movements to an internal source. 

 Bain holds that the refreshment of the nerve centres after 

 repose causes a " burst of spontaneous energy" and " a rush of 

 nervous power to the muscles, followed by the exposure of the 

 senses to the influence of the outer world" (66). The facts can be, I 

 think, interpreted differently and more consistently with general 



