1 Table of Contents: “... Expansions -- Let's learn about partial differentiation -- Epilogue: what is mathematics for?...”

2 Table of Contents: “... for a Diagrammatic Approach to the Question “What is Mathematics?” -- The Diagram: Demon of Proof...”

3 Table of Contents: “... Know About Mathematics -- by the Senior Year -- E.1 What is Mathematics to an Engineer? -- E.2...”