416 ON SENSORIAL VISION. 



always succeed, and requires a peculiar adjustment 

 of the light, and of the comparative illumination of the 

 objects and the ground on which it is seen projected, 

 and perhaps also a peculiar state of nerve ; but when it 

 does succeed, the effect is . exceedingly singular and 

 anomalous. 



(20.) It would lead me into too great a length of detail, 

 and I may also add, into a labyrinth of metaphysical 

 considerations, out of which I should find some diffi- 

 culty of getting disentangled, if I were to go into a dis- 

 cussion on those points of connexion between our 

 mental and our bodily organization which these facts 

 seem to suggest. There is a very curious chapter in 

 Stuart Mill's Treatise on Logic, devoted to the question 

 whether we are quite sure that every event has a cause. 

 He decides it, as every reasonable man must do, in 

 favour of the universality of the proposition, but he is 

 compelled to admit, as every one who considers it 

 closely must, I think, equally do, that the phsenomena 

 of the human will stand in a very peculiar relation to 

 that question ; and that granting volition to be a cause 

 of action, and granting the entire freedom of our will and 

 its complete independence to choose when a choice of 

 lines of action is brought before us, there is still the 

 question behind What determines the will] To this 

 question an answer must be found which will leave man 

 a moral and responsible agent. To choose the right 

 and to avoid the wrong, as such, must be left in his 

 power, and a freedom and independence of choice as 

 between these two grand lines of action must be left 



