272 APPENDIX A 



arguments, however, will not bear critical examination. 

 Emery and C. P. White seem to think that a continu- 

 ously progressing proliferation of malignant tissue de- 

 mands a continuously increasing irritant. This is surely 

 fallacious. If there is any loss of balance in a body or 

 any other structure, less and less power is needed to 

 cause destruction. The Leaning Tower of Pisa should 

 take less to overthrow it now than when it was built. 

 If the theory of organic restraint has any basis at all, 

 and no one can deny that it is very firmly based, any 

 such disaster as malignancy may be compared to a breach 

 made in a dam. To remove the highest part will 

 take much labour, but as water begins to flow potential 

 energy becomes kinetic, and the whole dam goes. In 

 malignancy we need not posit an increasing power, for 

 what we see in most cases is a decreasing resistance, as 

 every pathologist recognizes that there is attempted 

 repair in cancer, even though it mostly fails. Emery 

 also says, "if growth is very rapid, the innermost layer 

 of the epithelium may find it easier to grow downward 

 into the tissues than up." The italics are mine. The 

 developmental or hostile symbiotic view explains such 

 a fact. Indeed it shows that the necessary preliminary 

 to such downward growth is a failure of the connective 

 tissues which is plainly demonstrated by the pheno- 

 mena accompanying excessive radiation. With irri- 

 tated reacting epithelium it is not "may " but " must." 

 According to D'Este Emery malignant cells frequently 

 act as phagocytes, which suggests they have some power 

 of movement. This is surely a forced interpretation 

 of the destructive nature of malignant cells. That 

 they erode tissue, and even " eat away bone " 

 (Bland-Sutton) is true enough. But we do not call 



