On the Contrary: Disjunctive Syllogism and Pragmatic Strengthening (2015), p. 242
by Horn, Laurence

Copyright according to our policy

Caption

Jacoby’s geometries of opposition. From Paul Jacoby ([45], pp. 38 and 44) with permission from © 1950 Philosophy Documentation Center - Four Types of Simple Proposition

Logic

Number of labels per vertex (at most)

1

Errors in the diagram

No

Geometry

Shape

Trapezoid (irregular)

Colinearity range

0

Coplanarity range

0

Cospatiality range

0

Representation of contradiction

By central symmetry

Vertex description

Conceptual info

No

Mnemonic support (AEIO, purpurea ...)

Yes

Form

none

Label type

symbolic

Symbolic field

logic

Contains partial formulas or symbols

Yes

Logical system

syllogistics

Edge description

Contains definitions of relations

No

Form

solid lines

,

none

Has arrowheads

No

Overlap

No

Curved

No

Hooked

No

As wide as vertices

No

Label type

none

Style

Diagram is colored

No

Diagram is embellished

No