Onc service malhemalics has rendered Ihe "Et moil ...- si ravait au oomment en revcnir. je ny serais point aU: human race. It has put common sense back whcre it belongs, on the topmost shelf next Iules Verne to the dUlty canister IabeUed discarded n- sense. The series is divergent; therefore we may be Eric T. BeU able to do something with it. O. H eaviside Mathematics is a tool for thought, A highly necessary tool in a world where both feedback and non- linearities abound. Similarly, all kinds of parts of mathematics serve as tools for other pans 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 dare of this series.