You're using an ancient browser to surf the modern web. Please update to the latest version (and don't use Internet Explorer!).

Leonardi.DB
a logical geometry project

Things That are Right with the Traditional Square of Opposition (2008), p. 4
by Parsons, Terence

Logic

Aristotelian family
Classical Sigma-2
Boolean complexity
3
Number of labels per vertex (at most)
1
Uniqueness of the vertices up to logical equivalence
Yes
Errors in the diagram
No

Geometry

Shape
Rectangle (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 ...)
No
Form
none
Label type
linguistic
Language
English
Lexical field
syllogistics
Contains partial sentences or single words
No
Contains abbreviations
Yes

Edge description

Style

Diagram is colored
No
Diagram is embellished
No

Additional notes

This diagram only visualizes the relations that are explicitly discussed in Aristotle's Peri Hermeneias, viz., contradiction and contrariety. The relations of subcontrariety and subalternation can be derived from this.
↑ Back to top ↑