Icosa vs Four Temperaments
The Four Temperaments capture 82% of Icosa's capacity structure and represent Icosa's closest historical predecessor — every temperament maps completely to Icosa capacity clusters.
Overview
The Four Temperaments is the oldest formal personality classification system in recorded history, originating with Hippocrates (~400 BCE) and formalized by Galen (~200 CE) in the theory of humoral medicine. The four types — Sanguine, Choleric, Melancholic, and Phlegmatic — were originally attributed to physiological fluids (blood, yellow bile, black bile, phlegm) but have proven remarkably durable as descriptions of behavioral style. The framework reappeared in Kant’s anthropological writings, in Wundt’s two-axis model (strong/weak and changeable/stable), and persisted into 20th-century temperament research.
Icosa represents a mathematical formalization of the same underlying personality geometry that temperament theory has described qualitatively for 2,400 years. Every classical temperament maps completely to an Icosa capacity cluster with no gaps. This is not coincidental — Icosa’s capacity model was partly informed by the converging evidence from historical systems including this one.
What This Framework Captures
The Four Temperaments capture approximately 82% of Icosa’s capacity structure. Coverage weights:
- Capacities: 80% — Complete mapping. Sanguine = O+V+, Choleric = V+F+, Melancholic = F+B-V-, Phlegmatic = B+O-V-. Every Icosa capacity is represented across the four types, though no single type captures all capacities in a centered state.
- Domains: 52% — Partial. Relational and Emotional domain signatures are partially represented (Sanguine’s sociability → R domain, Melancholic’s sensitivity → E domain). Mental domain is partially represented via Melancholic’s analytical tendency. Physical domain is partially represented via Choleric’s hot-blooded energy and physical assertiveness. Spiritual domain is not represented.
- Coherence: 40% — Phlegmatic is historically described as the “most stable” temperament, which corresponds roughly to coherence, but temperament theory does not have a formal coherence construct.
- Traps: 15% — Classical descriptions of temperament excess (e.g., Melancholic’s slide into despair, Choleric’s rage) approach Icosa’s trap language but are not operationalized as structural patterns.
- Gateways: 10% — Not represented in classical temperament theory.
What This Framework Misses
Domain specificity. Classical temperament theory describes overall behavioral style but does not map how that style expresses differently across life domains. A Choleric person’s V+F+ pattern may be fully expressed in the Mental domain (intellectual drive) while collapsed in the Relational domain (authoritarian at work, absent in intimacy). Temperament theory has no language for this.
Coherence as a dynamic property. Temperament theory treats the four types as relatively fixed character descriptions. Icosa’s coherence score measures active integration across capacity clusters — a property that fluctuates over time and is responsive to growth interventions. This dynamic layer is absent.
Trap patterns. The classical descriptions of temperament imbalance (choleric anger, melancholic despair, phlegmatic stubbornness, sanguine recklessness) are qualitative observations without the structural precision of Icosa’s trap model, which specifies attractor geometry, oscillation signatures, and gateway blockage patterns.
Gateway dynamics. The interfaces between Icosa’s structural regions have no classical temperament analog.
Confidence Methodology
Base confidence: 0.82. The confidence is high due to the complete capacity mapping and the deep historical convergence between temperament theory and Icosa’s geometry.
Per-type confidence range: 0.82–0.84. Types are relatively uniform:
- Choleric: 0.83 (clear V+F+ mapping)
- Melancholic: 0.82 (F+B-V- mapping; weakest due to Emotional domain interpretation ambiguity)
- Phlegmatic: 0.83 (high B+ mapping with V- and O-)
- Sanguine: 0.84 (O+V+ mapping; strongest due to clear capacity expression)
Historical validation. The convergence of four temperament descriptions with Icosa’s capacity model across independently developed systems (temperament theory, DISC, Type A/B, Icosa) provides cross-system triangulation that strengthens confidence in the mapping.
Coverage Matrix
| Icosa Dimension | Temperament Coverage | Notes |
|---|---|---|
| Open capacity | 80% | Sanguine (over), Phlegmatic (under) |
| Move capacity | 85% | Choleric (over), Sanguine (over), Phlegmatic (under) |
| Focus capacity | 80% | Choleric (over), Melancholic (over), Phlegmatic (centered) |
| Bond capacity | 80% | Phlegmatic (over), Melancholic (under) |
| Physical domain | 25% | Choleric energy and action |
| Emotional domain | 50% | Melancholic sensitivity, Sanguine expression |
| Mental domain | 45% | Melancholic analytical depth |
| Relational domain | 60% | Sanguine and Phlegmatic warmth |
| Spiritual domain | 15% | Not directly represented |
| Coherence | 40% | Phlegmatic stability correlate |
| Traps | 15% | Qualitative excess descriptions only |
| Gateways | 10% | Not represented |
Type-by-Type Mapping
| Temperament | Primary Icosa Mapping | Confidence | Coherence Range |
|---|---|---|---|
| Sanguine | O+ over (0.85), V+ over (0.80), F+ under (0.45), B+ centered | 0.84 | 50–80 |
| Choleric | V+ over (0.90), F+ over (0.75), O+ under (0.50), B+ under (0.45) | 0.83 | 45–80 |
| Melancholic | F+ over (0.85), B+ under (0.60), V+ under (0.55), O+ centered | 0.82 | 40–75 |
| Phlegmatic | B+ over (0.85), O+ under (0.55), V+ under (0.60), F+ centered | 0.83 | 55–85 |
Capacity key: O=Open, V=Move, F=Focus, B=Bond. Domain key: P=Physical, E=Emotional, M=Mental, R=Relational, S=Spiritual.
Bidirectional Translation
Temperament → Icosa uses complete capacity cluster mapping. Because every temperament has a well-defined Icosa capacity signature, the initial translation is higher-confidence than most other frameworks. The primary limitation is that domain state (particularly Spiritual, Physical, and detailed Emotional structure) must be assessed directly — temperament type provides no anchor for these.
Example: A Melancholic profile translates to Icosa starting point of F+ elevated, B+ under, V+ under, O+ centered; Mental domain elevated; Emotional domain moderate. Spiritual domain, Physical domain, coherence, trap risk, and gateway states are unresolved.
Icosa → Temperament projects well for capacity-dominant profiles. Profiles where mixed capacity states are primary (e.g., equal B+ and V+ elevation) map ambiguously to temperament types. Classical temperament theory has no blend concept comparable to DISC’s blend types, so mixed Icosa profiles produce uncertain temperament assignments.
Historical Note
The persistence of temperament-like categories across independently developed personality frameworks — appearing in DISC (1928), MBTI (1944), Big Five (1980s), HEXACO, and Icosa — provides strong evidence that these four clusters represent genuine structural attractors in human personality space rather than arbitrary cultural constructs. Icosa’s contribution is to formalize what these systems have described qualitatively: the four temperaments correspond to four extreme positions in Icosa’s capacity space, with the centered state representing the balanced integration all four traditions identify as psychological health.
Known Gaps
No blend or mixed-temperament model. Classical temperament theory assigns one of four types. Icosa profiles with co-equal capacity elevations (e.g., V+ and B+ both elevated) map ambiguously because temperament theory has no blend concept comparable to DISC’s blend types or Holland’s two-letter codes.
Domain-level mapping is inferential. Temperament descriptions carry implicit domain associations (Melancholic’s analytical nature → Mental domain, Sanguine’s sociability → Relational domain), but these are inferred from behavioral style rather than directly theorized. Physical and Spiritual domain mappings are particularly weak.
Research Basis
- Hippocrates (~400 BCE). On the Nature of Man. (Attributed to Polybius, son-in-law of Hippocrates.)
- Galen (~190 CE). De temperamentis. On the temperament and its role in health and character.
- Wundt, W. (1903). Grundzüge der physiologischen Psychologie (5th ed.). Engelmann.
- Strelau, J. (1998). Temperament: A Psychological Perspective. Plenum Press.
- Icosa Validation Study (2026). Temperament-to-Icosa structural mapping: historical convergence analysis. Sanguine→O+V+ r=0.79, Choleric→V+F+ r=0.81, Melancholic→F+ r=0.77, Phlegmatic→B+ r=0.82.
Interactive Explorer
Select a Four Temperaments type below to see which Icosa centers it maps to. Switch between views to explore capacity targets, domain emphasis, and structural blind spots.
Choleric
Driven, decisive, ambitious, leader. Goal-oriented with strong will and quick temper.
- Mental domain depth
- Spiritual domain (limited)
- Trap patterns (not modeled)
- Coherence nuance (limited)
See how your profile translates
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