Oppositions and Opposites (2012), p. 164
by Schang, Fabien

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Caption

A complete set of local opposite-forming operators $N^k_j$ for Blanché’s double helix of logical oppositions

Logic

Aristotelian family

Sigma-5 Graph

Boolean complexity

4

Number of labels per vertex (at most)

1

Uniqueness of the vertices up to logical equivalence

No

Errors in the diagram

No

Geometry

Shape

Hexagon (irregular)

Colinearity range

0–2

Coplanarity range

1

Cospatiality range

0

Representation of contradiction

By some other geometric feature

Vertex description

Conceptual info

No

Mnemonic support (AEIO, purpurea ...)

No

Form

none

Label type

symbolic

Symbolic field

logic

Contains partial formulas or symbols

No

Logical system

propositional logic

Edge description

Style

Diagram is colored

No

Diagram is embellished

No

Has related diagram

Blanché, Robert. 1957. “Sur La Structuration du Tableau Des Connectifs Interpropositionnels Binaires.” Journal of Symbolic Logic 22 (1): 17–18. (p. 18)

Blanché, Robert. 1969. “Sur le système des connecteurs interpropositionnels.” Cahiers pour l’Analyse 10: 131–149. (p. 144)

Additional notes

From the CO-perspective, this is a C4O1 diagram. (Two strong JSB sigma-3's that are intertwined with each other.)