SELECTED PAPERS 



Dear Van Iterson, 

 That I, who have been privileged to be your long-time assistant, have 

 now been called upon to succeed him whose assistant you yourself 

 have been for many years, reminds me of the atavistic phenomena that 

 are so characteristic of certain higher plants, to use another biological 

 analogy. To me this is proof of the close relationship that exists be- 

 tween the subjects we are to teach. It seems to me that our teaching 

 will profit if at all times we inculcate a recognition of this relationship 

 into the future chemical engineers. It is for this reason, too, that I 

 here want to express the ardent hope that you may be found willing 

 to grant me your continued support, tutelage, and friendship which 

 you have so lavishly accorded me hitherto. Be convinced that I shall 

 always remember that it was you who showed me the way to inde- 

 pendent research. During the nearly six years that have elapsed since 

 I left your laboratory I have realized how much more you have im- 

 parted to me for life. 



My parents, 

 My presence here is certainly in no small measure the result of your 

 devoted cares. I feel fortunate that I may publicly thank you for this. 

 The education you gave me was characterized by acts of love rather 

 than by verbose theory. For that very reason I shall not expand this 

 fervent testimony. 



Ladies and gentlemen, students of the Technological University, 

 Even though so little time has gone by since the moment when I left 

 this university, I cannot claim that we are mutually acquainted. It is 

 probable that all of us will have changed too much during that brief 

 span. On the one hand, the war has also caused upheavals in the student 

 community whose significance I cannot yet fathom. On the other hand, 

 fate has taken me to far-away countries, and did not Goethe, in his 

 'Wahlverwandtschaften', say that 'Die Gesinnungen andern sich ge- 

 wiss in einem Lande, wo Elefante und Tiger zuhause sind'? 



It is true that I encountered neither elephants nor tigers in a free 

 state; but the emancipating influence exerted by life in a foreign en- 

 vironment has not worn off. But, although we may not yet be able to 

 meet as old acquaintances, I should like to express the hope that we 

 may soon have reached that stage. 



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