4Et moi, ..., si j'avait su comment en revenir, One service mathematics
has rendered the je n'y serais point alle.' human race. It has put
common sense back Jules Verne where it belongs, on the topmost shelf
next to the dusty canister labelled 'discarded non- The series is
divergent; therefore we may be sense'. able to do something withit. Eric
T. Bell O. Heaviside Mathematicsis a tool for thought. A highly
necessary tool in a world whereboth feedback and non- linearities
abound. Similarly, all kinds of parts of mathematics serve as tools for
other parts and for other sciences. Applying a simple rewriting rule to
the quote on the right above one finds such statements as: 'One service
topology has rendered mathematical physics ...'; 'One service logic has
rendered com- puter science ...'; 'One service category theory has
rendered mathematics ...'. All arguably true. And all statements
obtainable this way form part of the raison d' tre ofthis series.