THE CONTROL OF LIFE 89 



less successfully the various life processes 

 taken one at a time no one has made an 

 artificial cell which can imitate all these 

 life processes simultaneously. It is evi- 

 dent that the simplest living cell is a ma- 

 chine of great complexity. This is only 

 another way of saying that we have a 

 great many factors, or variables, to deal 

 with. If we can measure each of these 

 we may hope to arrive at a clear picture 

 of the life processes of a cell and to 

 express them in a definite manner, pref- 

 erably in mathematical form. If we can 

 do this we may also hope to predict the 

 course of life processes as w^e predict the 

 course of the tides, which also involves a 

 great many variables. We need not de- 

 spair of the power of the human mind 

 to deal with such a large number of 

 variables providing each of them can be 

 measured. 



Our task then is clearly defined. It 

 is to measure each of the factors or va- 

 riables which determine life processes to 

 the end that we may imitate, predict 



