Contents

Introduction

I The Five Platonic Solids (Answers on page 17)

2 Tetraflexagons

3 Henry Ernest Dudeney: England's Greatest Puzzlist (Answers on page 31)

4 Digital Roots (Answers on page 38)

5 Nine Problems (Answers on page 43)

6 The Soma Cube (Answers on page 59)

7 Recreational Topology (Answers on page 67)

8 Phi: The Golden Ratio (Answers on page 78)

9 The Monkey and the Coconuts (Answers on page 86)

10 Mazes

11 Recreational Logic (Answers on page 101)

12 Magic Squares

13 James Hugh Riley Shows, Inc. (Answers on page 116)

14 Nine More Problems (Answers on page 123)

15 Eleusis: The Induction Game (Answers on page 135)

16 Origami (Answers on page 144)

17 Squaring the Square

18 Mechanical Puzzles (Answers on page 169)

19 Probability and Ambiguity (Answers on page 178)

References for Further Reading

English