Machine generated contents note: I. Philosophical Introduction 1 -- 1. Truth 3 -- 2. Definition 15 -- 3. Reconceptualization 35 -- 4. Foundations 41 -- 5. The Identity of Abstracts 46 -- II. The Context Principle 55 -- 1. What is the Context Principle? 56 -- 2. Completeness 60 -- 3. The Caesar Problem 68 -- 4. Referential Determinacy 77 -- 5. Predicativity 81 -- 6. The Possible Predicative Content of Hume's Law 90 -- III. The Analysis of Acceptability 101 -- 1. Language and Logic 101 -- 2. Models 105 -- 3. Preliminary Results 107 -- 4. Tenability 114 -- 5. Generation 118 -- 6. Categoricity 122 -- 7. Invariance 138 -- 8. Hyperinflation 156 -- 9. Internalized Proofs 161 -- IV. The General Theory of Abstraction 165 -- 1. The Systems 165 -- 2. Semantics 175 -- 3. Derivations 189 -- 4. Further Work 191