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

Duality Patterns in 2-PCD Fragments (2017), p. 246
by Smessaert, Hans; Demey, Lorenz

Caption

Example of the $\textit{mixed self-internal/self-dual}$ degenerate (SISD) duality pattern: (a) degenerate square for the fragment $\mathcal{F}$, (b) self-internal collapsed square for $\delta^*(\pi_\alpha)$, (c) self-dual collapsed square for $\delta^*(\pi_\beta)$, (d) octagon for the fragment $\mathcal{F}^*$.

Logic

Aristotelian family
Degenerate Sigma-2 with Unconnectedness 4
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
Octagon (regular)
Colinearity range
0
Coplanarity range
0
Cospatiality range
0
Representation of contradiction
By central symmetry

Vertex description

Conceptual info
Yes
Mnemonic support (AEIO, purpurea ...)
No
Form
dots
Label type
symbolic
Symbolic field
logic
Contains partial formulas or symbols
No
Logical system
modal logic

Edge description

Contains definitions of relations
No
Form
dash-double-dotted lines
,
solid lines
,
dash-dotted lines
,
none
Has arrowheads
No
Overlap
No
Curved
No
Hooked
No
As wide as vertices
No
Contains text
No
Label type
none

Style

Diagram is colored
No
Diagram is embellished
No
Tags
Leuven
;
duality
↑ Back to top ↑