1. Introduction -- 2. Areas and Angles -- 3. Tessellations and Symmetry -- 4. The Postulate of Closest Approach -- 5. The Coexistence of Rotocenters -- 6. A Diophantine Equation and its Solutions -- 7. Enantiomorphy -- 8. Symmetry Elements in the Plane -- 9. Pentagonal Tessellations -- 10. Hexagonal Tessellations -- 11. Dirichlet Domain -- 12. Points and Regions -- 13. A Look at Infinity -- 14. An Irrational Number -- 15. The Notation of Calculus -- 16. Integrals and Logarithms -- 17. Growth Functions -- 18. Sigmoids and the Seventh-year Trifurcation, a Metaphor -- 19. Dynamic Symmetry and Fibonacci Numbers -- 20. The Golden Triangle -- 21. Quasi Symmetry -- Appendix I: Exercise in Glide Symmetry -- Appendix II: Construction of Logarithmic Spiral.