The Elements of Logic. A Text-book for Schools and Colleges (1883), p. 83
by Jevons, William Stanley; Hill, David J. (ed.)

Copyright according to our policy

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

Square (regular)

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

Edge description

Style

Diagram is colored

No

Diagram is embellished

No