PROTOPLASM. 21 



and the matter of life of the Crustacea would undergo 

 the same wonderful metamorphosis into humanity. 

 And were I to return to my own place by sea and 

 undergo shipwreck the Crustacea might and prob- 

 ably would return the compliment and demonstrate 

 our common nature by turning my protoplasm into 

 living lobster." 



The medical student is here reminded of the con- 

 stant warfare being waged between many forms of 

 living matter. We acknowledge today that most 

 of the diseases to which mankind is an heir and a 

 victim are nothing else than vicious attacks upon 

 us by some form of living matter. Tuberculosis, 

 pneumonia, diphtheria, typhoid, tetanus, cholera, 

 bubonic plague, and many other serious and fatal 

 diseases are now directly traced to invasions of mi- 

 cro-organisms, truly living things. Self-preservation 

 is nature's first law and it is God's law. Protective 

 selfishness and the preservation of a race, whatever 

 be the sacrifice, is a fundamental principle deeply 

 implanted in every form of living organism. There 

 is, therefore, no mercy shown in this warfare. There 

 is no hope of peace in this conflict, nay, not even a 

 respite, and sooner or later practically each one of 

 us must fall a victim to the enemy's invasion. 



The discovery of the germ origin of disease has 

 placed the study of medicine on a new and substantial 

 scientific basis. Not satisfied with merely a defensive 

 program, this warfare, by means of preventive med- 

 icine, has assumed the offensive to such a degree that 

 the disease scourges which in the past sometimes de- 

 cimated a people are today an impossibility. 



