SEC. 3. ON VOLUNTARY MOVEMENTS. 



482. When we examine ourselves we recognize certain of 

 our movements as * voluntary ' ; we say that we carry them out 

 by an effort of the ' will.' And when we witness the movements 

 of other people or of animals we regard as also voluntary such 

 of those movements as by their characters and by the circum- 

 stances of their occurrence seem to be carried out in the same 

 way as our own voluntary movements. Even in the case of some 

 of our own movements we are not always clear whether they uiv 

 really voluntary or no ; and in the case of other people and of 

 animals it is still more difficult to decide the question. It would 

 be out of place to attempt to discuss here how voluntary move- 

 ments really differ from involuntary movements, or in other 

 words, what is the nature of the will ; we must be content to take 

 a somewhat rough use of the words ' voluntary,' ' volitional,' and 

 'will' as a basis for physiological discussion. We may however 

 remark that so far as the muscular side of the act, if we may use 

 such an expression, is concerned, a voluntary movement does not 

 differ in kind from an involuntary movement. It is perfectly 

 true that a skilled man may by practice learn to execute mus- 

 cular manoeuvres which he would not have learnt to execute had 

 not an intelligent volition been operative within him ; but our 

 own experience teaches us that many more or less intricate move- 

 ments which have undoubtedly been learnt by help of the will 

 may be carried out under circumstances of such a kind that we 

 feel compelled to regard them as, at the time, involuntary : and 

 it may at least be debated whether every movement which we 

 can carry out, by an effort of the will, may not appear under 

 appropriate circumstances as part of an involuntary act. In tlu> 

 case of the lower animals, in the frog deprived of its cerebral 

 hemispheres for instance, we have seen that voluntary differ from 

 involuntary movements, not by their essential nature but by the 

 relation which their occurrence Kvirs to circumstances. We have 

 therefore to seek for the distinction between voluntary and in- 

 voluntary, not in the coordination of the muscular and nervous 

 components of a movement, but in the nature of the process 

 which starts the whole act. 



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