Chapter 1 Bolzano Against Kant’s Pure Intuition

Chapter 2 Poincaré on the Foundation of Geometry in the Understanding

Chapter 3 Natural Deduction for Diagonal Operators

Chapter 4 What is a Symbol?

Chapter 6 Magic Squares of Subtraction of Adam Adamandy Kochański

Chapter 7 Euler’s E228: Primality Testing and Factoring via Sums of Squares

Chapter 8 “A Most Elegant Property”: On the Early History of Lexell’s Theorem

Chapter 9 The Misnamings of Playfair’s Axiom

Chapter 10 Napier, Torporley, Menelaus, and Ptolemy: Delambre and De Morgan’s Observations on Seventeenth-Century Restructuring of Spherical Trigonometry

Chapter 11 The Reception of American Mathematics Education in Soviet Pedagogical Journals of the 1960s and 1970s

Chapter 12 Mathematics in Library Subject Classification Systems

Chapter 13 The Convolution as a Mathematical Object

Chapter 14 Sundials–Une Promenade Parisienne (A Math Walk in Paris)