LIFE OF ELIE METCHNIKOFF 235 



realised in these latter days, it is still powerless against a 

 multitude of diseases, threatening us on all sides. 



Pulmonary lesions (tuberculosis, pneumonia, etc.), the 

 nephrites, and an infinite quantity of other diseases can 

 yet neither be prevented nor cured. So we live in constant 

 fear for those we love. When medicine shall (as I am per- 

 suaded) have conquered all these evils, one cause of the 

 bitterness of life will cease but that is not yet the case. 



That is why, besides the weakening of the life-instinct, a 

 resignation towards death grows in us, as a means of no 

 longer feeling the ills which afflict our neighbours. 



With time, when that source of unhappiness has been 

 eliminated by medicine, old age will be more attractive, and 

 an orthobiotic life will become normal and realisable. 



At the ages of 50, 60, 65, I felt an intense joy in 

 living, such as I described in my Studies on Human Nature 

 and Optimistic Essays. In the last few years it has lessened 

 markedly. 



Scientific work still provokes in me an invincible enthusi- 

 asm, but I am becoming more indifferent to many of the 

 pleasures of life. 



And indeed he no longer had the joyous soul of 

 former days ; into his life a funereal note had crept, 

 low but continuous and obstinate. He gave all the 

 more energy to the study of those questions the 

 solution of which was to bring about the reign of 

 orthobiosis. He spent the whole winter in researches 

 on the intestinal flora and on the completion of his 

 studies on infantile cholera. 



In the spring, on the occasion of his anniversary, 

 he wrote the following : 



SEVRES, 16th May 1914. 



I have to-day entered my 70th year ; it is a great event 

 for me. As I analyse my feelings, I realise more and more 

 the weakening o/my " life-instinct." 



In order to verify my impressions, I wished to hear again 



