OUTLINE 13 



(A) From the point of view of its objective manifestations 

 as a whole, that is to say, as an entire organized indi- 

 vidual, either isolated or in its normal environment: 

 zoology, descriptive botany, etc. 



(B) From the point of view of the mechanisms of the 

 biological actions, using what we might call the breaking- 

 down methods. Either dynamic, i.e. maintaining life 

 and entailing no serious alterations in the part played 

 by each mechanism in particular (physiology); or else 

 static methods, which start by destroying life (cytology, 

 etc.). 



(C) From the purely physical and chemical point of view, 

 namely, by suppressing conventionally the difference 

 which distinguishes living from dead matter, and by 

 incorporating Ufe with our material universe. 



In the first case the unit will be the individual; in the second, 

 the cell; and in the third, the molecule. It can be seen that each 

 class corresponds to a different order of magnitude, therefore 

 to different methods of investigation. If we admit the 

 beautiful definition of Ch. E. Guye: '/r is the order of magni- 

 tude that creates the pheno??iena\ we shall be in each case 

 confronted by different phenomena. 



2. We will study in detail a fundamental biological phenome- 

 non: cellular reparation. First, under its best-known and most 

 important practical aspect, cicatrization of wounds; secondly, 

 under the experimental aspect given it by Dr. Carrel: tissue- 

 culture in vitro. We will discuss the mathematical con- 

 sequences which can be derived from the experiments and 

 which introduce a particular concept of age and time. 



3. Having introduced quantitatively the notion of time in 

 the experiments previously described, we will develop the 

 subject by explaining the conventional and relativistic concept 

 of time and its classical measurement. 



4. Finally, we will develop the concept of duration and of 

 physiological time. Contrary to the customary procedure, we 

 will borrow a unit from our inteimal time, and we will use it 



