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by a set of motor nerves, to the muscles of a limb. 

 Here continuity in the history of the executed move 

 ment is manifest. This is illustrated in the action of 

 all organic life. Again, the facts stand in contrast with 

 continuity observed in co-ordination within brain- 

 structure. Thus, double organs of special sense are 

 co-ordinated so as to give a unified result from the 

 action of two separate nerve-fibres brought into 

 relation within the brain. But the conception of 

 an object is not a continuance of sensory action. 

 Conceptions of objects do not flow in upon the mind. 

 They are made up by the mind through action of com 

 parison, while utilising a past experience. We receive 

 our impressions ; we make our conceptions. Accord 

 ingly, Ave see many things of which we form no 

 conceptions. Conceptions are often reconstructed, as 

 the result of fresh observation. This severance from 

 sensible experience becomes more manifest, when 

 rational inductions are included, as when we recognise 

 the law of gravitation, conservation of energy, or 

 natural selection. These things do not arise in con 

 sciousness, as muscular movements are executed in 

 response to sensory impression. Thought has a 

 history very different, requiring a distinct explana 

 tion. 



Here the psychology of evolution seems insufficient. 

 Darwin has given a considerable gathering of pheno 

 mena, well summarised by Wallace. A glance may 

 suffice to show the variety included. Within Part I. 

 of The Descent of Man, which alone is devoted to the 

 descent or origin of man, we have extended illustration 

 of the analogies of animal and human experience and 

 action. Special value belongs to the facts gathered by 



