CHEMICAL CHARACTERS OF CELL 47 



the most recent and most able writers on the subject, 

 M. Le Dantec, 1 it will now be necessary to deal. 



Spontaneity of movement, he tells us, is not an 

 essential character of life. "If we observe with 

 no other help than what nature affords all that goes 

 on round about us, it will seem evident that the 

 mouse moves in conditions where a stone of the 

 same dimension and situated in the same place 

 would remain motionless. In other words, where 

 the stone's immobility shows that there is no cause 

 of movement (wind, water-current, etc.), a mouse 

 displaces itself spontaneously" 



If we reasoned more closely, we should say : 

 " Where the stone's immobility shows there is no 

 displacing cause for the stone, the mouse's move- 

 ment, on the contrary, should make us think either 

 the mouse is endowed with spontaneous mobility, 

 or at the point where it is placed there is some 

 cause of movement /or the mouse" 



This no doubt is perfectly true, but the real 

 heart of the matter is the nexus between the cause 

 of movement and the movement itself. It is clear 

 that the nexus might be physical, since some one 

 might pick up the mouse and throw it away. It is 

 .conceivable that it might be chemical, since we could 

 imagine a condition of affairs in which contact, say, 



1 Op. cit. t p. 157. Italics in quotations from this author are 

 as in original. 



