VIEWPOINTS IN THE STUDY OF GROWTRi 



LAFAYETTE B. MENDEL 



From whatever Standpoint the Student of science considers liv- 

 ing organisms he soon learns that there are certain fundamental 

 characteristics peculiar to their protoplasm and distinguishing it 

 from what is commonly termed unorganized matter. Life without 

 growth and activity, without the power of " automatic development, 

 self-preservation, and reproduction," is at present inconceivable. 

 Whether or not the artificial production of hving matter from that 

 which is hfeless may some day be accomplished need not concern us 

 now. As Karl Pearson has written: "There is mystery enough 

 here, only let us clearly distinguish it from ignorance within the 

 field of possible knowledge. The one is impenetrable, the other we 

 are daily subduing." 



I have termed the subject of this review " viewpoints " to empha- 

 size what is all too frequently forgotten, namely, that the data of 

 science are continually changing as the result of the addition of new 

 facts and the modification of the known. Such changes bring with 

 them new sequences — they compel us to new conclusions and sug- 

 gest new inquiries. Donaldson recently remarked that : " The atti- 

 tude toward knowledge during our student days is almost neces- 

 sarily such as to throw the idea of change into the background and 

 unduly emphasize the permanency of the things taught. The facts 

 are otherwise" (Science, July 25, 1913, p. 109.) Furthermore, it 

 is quite as important for the scientific investigator to formulate 

 clearly the problems which his experience dictates as to be con- 

 cerned solely with his experimental researches. (I confess, how- 

 ever, that I often feel sympathy with a remark attributed to the 

 late Professor Atwater, that his idea of a scientific man's heaven 



1 This paper was read in part at the third annual dinner of the Columbia 

 University Biochemical Association in New York City, November 21, 1913; sub- 

 sequently, also, before the local chapters of the Society of the Sigma Xi at the 

 University of Kansas, the University of Missouri, and Washington University, 

 St. Louis. The charts and photographs are not reproduced here. 



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