Category Theory Structure Rank Skill
Ranked taxonomy of categorical structures from sets to ∞-topoi with gap analysis and DuckDB integration.
Trit: 0 (ERGODIC) — Coordinator mapping structures to skills
Structure Hierarchy
Level 0: Foundations
| Structure |
Skill |
Coverage |
Gap |
| Sets |
(implicit) |
✓ |
— |
| Functions |
(implicit) |
✓ |
— |
| Relations |
acsets-relational-thinking |
✓ |
— |
Level 1: Basic Categories
| Structure |
Skill |
Coverage |
Gap |
| Categories |
ctp-yoneda |
✓ |
— |
| Functors |
naturality-factor |
✓ |
— |
| Natural Transformations |
naturality-factor |
✓ |
— |
| Yoneda Lemma |
yoneda-directed |
✓ |
— |
Level 2: Enriched & Internal
| Structure |
Skill |
Coverage |
Gap |
| Enriched Categories |
elements-infinity-cats |
◐ |
Need dedicated skill |
| Monads |
free-monad-gen |
✓ |
— |
| Adjunctions |
galois-connections |
✓ |
— |
| Elementary Topoi |
effective-topos |
✓ |
— |
Level 3: Higher Structures
| Structure |
Skill |
Coverage |
Gap |
| Double Categories |
cat-tripartite |
◐ |
Partial in CatColab |
| Bicategories |
— |
✗ |
MAJOR GAP |
| Operads |
operad-compose |
✓ |
— |
| Polynomial Functors |
asi-polynomial-operads |
◐ |
Spivak lectures incomplete |
| Actegories |
unwiring-arena |
◐ |
Implicit only |
Level 4: Homotopical
| Structure |
Skill |
Coverage |
Gap |
| Quasi-categories |
elements-infinity-cats |
✓ |
— |
| Segal Spaces |
segal-types |
✓ |
— |
| Complete Segal Spaces |
rezk-types |
✓ |
— |
| ∞-Cosmos |
elements-infinity-cats |
✓ |
— |
| Dendroidal Sets |
infinity-operads |
◐ |
Need formalization |
Level 5: ∞-Topoi
| Structure |
Skill |
Coverage |
Gap |
| ∞-Categories |
infinity-topos |
✓ |
— |
| ∞-Topoi |
infinity-topos |
✓ |
— |
| Higher Topos Theory |
infinity-topos |
◐ |
Lurie's HTT not fully extracted |
| Synthetic ∞-Cat |
riehl-post-rigorous |
◐ |
Rzk formalization ongoing |
Coverage Legend
✓ = Good coverage (skill exists, comprehensive)
◐ = Partial coverage (skill exists, gaps remain)
✗ = No coverage (major gap, needs skill)
Major Gaps Identified
1. Bicategories (Level 3)
Status: ✗ No dedicated skill
Impact: High — bridges double categories and ∞-cosmos
Remedy: Create bicategory skill from:
- Street's "Fibrations in Bicategories"
- Bénabou's original work
- Link to
cat-tripartite and topos-catcolab
2. Polynomial Functors (Level 3)
Status: ◐ Partial in asi-polynomial-operads
Impact: High — Spivak's key contribution
DuckDB: /Users/bob/ies/spivak_poly.duckdb (empty lectures table)
Remedy: Extract from Spivak lectures, populate DuckDB
3. Dendroidal Sets (Level 4)
Status: ◐ Mentioned but not formalized
Impact: Medium — ∞-operads foundation
Remedy: Create dedicated skill with:
- Moerdijk-Weiss construction
- Link to
infinity-operads
4. HTT Extraction (Level 5)
Status: ◐ Lurie's Higher Topos Theory not fully extracted
Impact: Very High — foundational reference
Remedy: MathPix extraction of key chapters
DuckDB Sources
| Database |
Tables |
Relevance |
hatchery_category.duckdb |
concept_graph, concept_paths |
Concept relationships |
spivak_poly.duckdb |
spivak_poly_lectures |
Polynomial functors |
dendroidal.duckdb |
dendroidal |
Tree structures |
mermaid_acset.duckdb |
— |
Diagram persistence |
hatchery_topology.duckdb |
— |
Topological structures |
Query: Concept Graph
-- Find category-theoretic concepts
SELECT source_concept, relation, target_concept
FROM concept_graph
WHERE source_concept IN ('Actegory', 'Dendroidal Sets', 'Galois Connection')
ORDER BY source_concept;
Query: Structure Dependencies
-- Build structure dependency graph
WITH RECURSIVE deps AS (
SELECT source_concept, target_concept, 1 as depth
FROM concept_graph
WHERE source_concept = 'Dendroidal Sets'
UNION ALL
SELECT g.source_concept, g.target_concept, d.depth + 1
FROM concept_graph g
JOIN deps d ON g.source_concept = d.target_concept
WHERE d.depth < 5
)
SELECT * FROM deps;
GF(3) Trit Assignment by Level
| Level |
Trit |
Role |
Example |
| 0-1 |
-1 |
Foundation/Constraint |
Sets, Categories |
| 2-3 |
0 |
Transport/Enrichment |
Monads, Operads |
| 4-5 |
+1 |
Generation/Extension |
∞-Categories, Synthetic |
Conservation: Each level transition preserves GF(3) sum.
Intercept Points (SNPs = Skill Navigation Points)
High-Value Intercepts
| From |
To |
Skill Bridge |
Value |
| Operads → ∞-Operads |
operad-compose → infinity-operads |
Dendroidal embedding |
★★★ |
| Topos → ∞-Topos |
effective-topos → infinity-topos |
Lurie characterization |
★★★ |
| Adjunction → Kan Extension |
galois-connections → kan-extensions |
Universal property |
★★★ |
| Double Cat → ∞-Cosmos |
cat-tripartite → elements-infinity-cats |
Formal category theory |
★★ |
| Polynomial → Operad |
asi-polynomial-operads → operad-compose |
Spivak construction |
★★ |
Unclear/Disputed Areas
| Area |
Issue |
Skills Involved |
| Model independence |
When does ∞-cosmos suffice vs concrete model? |
riehl-post-rigorous, elements-infinity-cats |
| Synthetic foundations |
HoTT vs Book HoTT vs Rzk |
riehl-post-rigorous, segal-types |
| Operad coloring |
GF(3) vs arbitrary coloring for operads |
infinity-operads, gay-mcp |
| Actegory ↔ Module |
Terminological confusion |
unwiring-arena, operad-compose |
Grandis/Grossberg Connections
Marco Grandis (Directed Algebraic Topology)
- d-spaces: Spaces with distinguished directed paths
- Link:
directed-interval, covariant-fibrations
- Gap: No dedicated Grandis skill
Steven Grossberg (Adaptive Resonance Theory)
- ART: Attractor dynamics in neural networks
- Link:
alife, attractor, equilibrium
- Gap: Need bridge to categorical learning theory
Skill Creation Priority
| Priority |
Gap |
Estimated Effort |
| 1 |
Bicategories |
Medium |
| 2 |
Polynomial functors (complete) |
High |
| 3 |
HTT extraction |
Very High |
| 4 |
Dendroidal formalization |
Medium |
| 5 |
Grandis d-spaces |
Low |
Commands
# Query concept graph
duckdb /Users/bob/ies/hatchery_category.duckdb \
-c "SELECT * FROM concept_graph WHERE relation = 'uses';"
# Check Spivak lectures
duckdb /Users/bob/ies/spivak_poly.duckdb \
-c "SELECT COUNT(*) FROM spivak_poly_lectures;"
# Find skill gaps
grep -l "TODO\|FIXME\|GAP" ~/.claude/skills/*/SKILL.md
Related Skills
ctp-yoneda - Basic category theory
elements-infinity-cats - Riehl-Verity ∞-cosmos
infinity-topos - ∞-topos integration
operad-compose - Operadic composition
riehl-post-rigorous - Formalization strategies
asi-polynomial-operads - Polynomial/operad bridge
Autopoietic Marginalia
The interaction IS the skill improving itself.
Every use of this skill is an opportunity for worlding:
- MEMORY (-1): Record what was learned
- REMEMBERING (0): Connect patterns to other skills
- WORLDING (+1): Evolve the skill based on use
Add Interaction Exemplars here as the skill is used.