Notation and Conventions
Aa
This page collects the notation used throughout the book. Mathematical symbols follow standard conventions where they exist; departures are noted.
Logic and Derivability
| Symbol | Meaning |
|---|---|
| Syntactic derivability: means is provable from | |
| Not derivable: means is not provable from | |
| Semantic satisfaction: means model satisfies | |
| Contradiction / falsity | |
| Negation of | |
| Conjunction | |
| Disjunction | |
| Implication |
Set and Type Notation
| Symbol | Meaning |
|---|---|
| Membership | |
| Subset (inclusive) | |
| Empty set | |
| Type of witnesses for proposition | |
| Witness has type "evidence for " |
Equivalence and Identity
| Symbol | Meaning |
|---|---|
| Equality in the stated mathematical setting; type-identity judgments are identified where used | |
| Isomorphism: structure-preserving bijection with explicit inverse | |
| Equivalence in the declared setting: categorical equivalence uses inverse functors up to natural isomorphism; HoTT passages use type equivalence | |
| Scoped equivalence: means and are equivalent in scope |
Convention: A10/A16 operational equivalence records declare scope and the properties they support. Mathematical equivalences are interpreted under their stated objects, ambient theory and hypotheses.
Category Theory
| Symbol | Meaning |
|---|---|
| Morphism from to | |
| Composition: apply first, then | |
| Identity morphism on | |
| Functor from category to | |
| Adjunction: is left adjoint to | |
| Set of morphisms from to |
Schemas and Signatures
| Symbol | Meaning |
|---|---|
| Signature: types + predicates + constraints | |
| Signature with constraint set | |
| Model satisfies signature under constraints | |
| Signature morphism; vocabulary inclusion is a special case | |
| Local theory at context : including logic choice |
A3 uses the schema shorthand , including integrity constraints. The displayed theory notation exposes that constraint component separately; it does not add a second set of constraints. In comparisons of theories, the vocabulary and governing constraints must both be identified.
Contexts and Covers
| Symbol | Meaning |
|---|---|
| Contexts (views, perspectives, local frames) | |
| Cover of by family of contexts | |
| Restriction of section to context | |
| Overlap of contexts (where gluing conditions apply) |
Commitment and Provenance
| Symbol | Meaning |
|---|---|
| Commitment set (propositions the system has asserted) | |
| Commitment set is consistent | |
| Witnessed assertion: claim with witness | |
| Under context , is evidence for |
Anchors (A1–A32)
Formal definitions are marked with anchor identifiers. Later chapters depend on these definitions and on the order in which they appear.
Numbering convention:
- Primary anchors: A1, A2, A3, ...
- Sub-anchors: A2b, A2c, A12b, etc. (refinements or components of a primary anchor)
- Status: formal (definition, written statement or construction), preformal (requirement awaiting a model), or engineering (proposed operational discipline)
The dependency graph is acyclic by construction. Appendix F contains the full anchor registry with formal statements and dependencies.
Touchstones (T1–T10)
The ten touchstones are recurring questions and worked examples, including constructed cases. They connect the definitions to operations a reader can examine. Their conclusions depend on the stated representation and hypotheses; they are not empirical proof that every system needs this architecture.
| ID | Name | Domain | One-Line Description |
|---|---|---|---|
| T1 | Contradiction | String | Query for impossible objects (primes divisible by 4) |
| T2 | Reference | String | Same referent, different surface (morning star / evening star) |
| T3 | Compositionality | String | Systematic generalization (SCAN-style "add jump") |
| T4 | Exactness | String | Discrete quantities (counting, arithmetic) |
| T5 | Negation/Absence | String | Category boundaries, exceptions (flying mammals) |
| T6 | Predicate Invention | Relational | New dimension on demand ("puffy dress") |
| T7 | Contextual Equivalence | Both | Same sometimes, not always (NYC vs New York City) |
| T8 | Uncertainty/Value | Relational | Non-factual targets ("best restaurant") |
| T9 | Schema Evolution | Relational | Vocabulary drift over time (employees → workers) |
| T10 | Higher-Arity Events | Relational | N-ary meaning ("Alice introduced Bob to Carol") |
Each touchstone maps to required artifacts and resolving anchors. The full registry appears in Appendix E.
General Conventions
Written statements, constructions and open problems retain their stated status. Appendix K.8 identifies the machine-checked declarations separately.
Logic choice: Different contexts may operate under different logics (classical vs. intuitionistic). When logic matters, it is stated explicitly. Local theory includes the logic .
Running examples: The fashion catalog domain (dresses, predicates like "puffy," equivalences like "blue" vs. "navy") serves as the primary worked example throughout.