This Film is Background for: Basic Principles for Real Numbers Part III and Part IV e_mb_0016, e_mb_001 Numerical Variables: Developing the Concept e_mb_0020 Bound Variables: Matching Language with Awareness e_mb_0021 Prelude to Deduction e_mb_0023 Substitution and the Linking Rule e_mb_0024 Proving Generalization e_mb_0026, e_mb_0027 Principles and Discovery in Algebraic Manipulation e_mb_0029, e_mb_0030