'Et moi, ... , si j'avait so comment CD revenir. je One service mathematics bas rendered !be human race. It bas put common sense back n 'y semis point aile.' JulesVeme where it belongs, on !be topmost shelf next to !be dusty canister labelled 'discarded nonsense'. Erie T. Bell The series is divergent; therefore we may be able to do something wilh it O. Heaviside Mathematics is a tool for thought. A highly necessary tool in a world where both feedback and nonlineari ties abound. Similarly, all kinds of parts of mathematics serve as tools for other parts and for other sci ences. Applying a simple rewriting rule to the quote on the right above one finds such statements as: 'One ser .. .'; 'One service logic has rendered computer science vice topology has rendered mathematical physics .. .'; 'One service category theory has rendered mathematics .. .'. All arguably true. And all statements obtainable this way form part of the raison d'8tre of this series.