I Origins of Formal Structure.- 1. The Natural Numbers.- 2. Infinite Sets.- 3. Permutations.- 4. Time and Order.- 5. Space and Motion.- 6. Symmetry.- 7. Transformation Groups.- 8. Groups.- 9. Boolean Algebra.- 10. Calculus, Continuity, and Topology.- 11. Human Activity and Ideas.- 12. Mathematical Activities.- 13. Axiomatic Structure.- II From Whole Numbers to Rational Numbers.- 1. Properties of Natural Numbers.- 2. The Peano Postulates.- 3. Natural Numbers Described by Recursion.- 4. Number Theory.- 5. Integers.- 6. Rational Numbers.- 7. Congruence.- 8. Cardinal Numbers.- 9. Ordinal Numbers.- 10. What Are Numbers?.- III Geometry.- 1. Spatial Activities.- 2. Proofs without Figures.- 3. The Parallel Axiom.- 4. Hyperbolic Geometry.- 5. Elliptic Geometry.- 6. Geometric Magnitude.- 7. Geometry by Motion.- 8. Orientation.- 9. Groups in Geometry.- 10. Geometry by Groups.- 11. Solid Geometry.- 12. Is Geometry a Science?.- IV Real Numbers.- 1. Measures of Magnitude.- 2. Magnitude as a Geometric Measure.- 3. Manipulations of Magnitudes.- 4. Comparison of Magnitudes.- 5. Axioms for the Reals.- 6. Arithmetic Construction of the Reals.- 7. Vector Geometry.- 8. Analytic Geometry.- 9. Trigonometry.- 10. Complex Numbers.- 11. Stereographic Projection and Infinity.- 12. Are Imaginary Numbers Real?.- 13. Abstract Algebra Revealed.- 14. The Quaternionsand Beyond.- 15. Summary.- V Functions, Transformations, and Groups.- 1. Types of Functions.- 2. Maps.- 3. What Is a Function?.- 4. Functions as Sets of Pairs.- 5. Transformation Groups.- 6. Groups.- 7. Galois Theory.- 8. Constructions of Groups.- 9. Simple Groups.- 10. Summary: Ideas of Image and Composition.- VI Concepts of Calculus.- 1. Origins.- 2. Integration.- 3. Derivatives.- 4. The Fundamental Theorem of the Integral Calculus.- 5. Keplers Laws and Newtons Laws.- 6. Differential Equations.- 7. Foundations of Calculus.- 8. Approximations and Taylors Series.- 9. Partial Derivatives.- 10. Differential Forms.- 11. Calculus BecomelÅ