168 APPLICATION TO CANCER RESEARCH 



When a child grows to form a man he grows by the 

 multiplication of his cells, but we did not know what 

 causes him to grow, or what makes his cells to attain 

 this object. 



Again, if we injure or wound ourselves in any part 

 of the body, the tissues always make an attempt to 

 repair the damage. No matter to what extent the 

 injury may occur, attempted healing always takes 

 place. The phenomenon of healing is due to the 

 proliferation of white blood-cells, which multiply by 

 cell-division to repair the tissues which are damaged. 

 Not only do leucocytes and lymphocytes proliferate 

 when a tissue is damaged, but other cells also multiply. 

 For instance, epithelial cells will also proliferate to heal 

 a damaged site. The cell-proliferation of healing forms 

 one of the bases of pathology, and therefore of medicine 

 also; yet it had to be admitted that nothing whatever 

 was known as to why this cell-proliferation occurs when 

 any part of our bodies is damaged. The process of 

 healing is occurring in our bodies throughout our lives, 

 and this sudden multiplication of cells must be con- 

 stantly before the consideration of medical men; but 

 although this multiplication by reproduction is an 

 established fact, one never hears the question asked, 

 Why do cells immediately divide to reproduce them- 

 selves when a tissue is damaged ? If the question was 

 asked, however, the answer would have had to be, 

 "We do not know." 



For the cell-proliferation of healing to occur it is. 

 not necessary for the skin to be actually broken. On 

 the contrary, extensive cell-proliferation of healing may 



