Subject and Predicates

“A Chu space is a set X of subjects and a set A of predicates on those subjects. These stand in a symbiotic relationship in which the nature of each is determined by the other. Each subject is characterized by the values the predicates take on it, while each predicate is characterized by its values on subjects.”

— Vaughan Pratt, Chu Spaces

Sambin's Basic Picture

Click here for Sambin’s paper (ps).

It would seem that Pratt and Sambin need to reconcile their similar predicates for the same subject.

For some background on Sambin’s approach to the subject, see

Mathematical Modal Logic:
A View of its Evolution (pdf),
by Robert Goldblatt at
Victoria University of Wellington’s
Centre for Logic, Language,
and Computation

For some background on Pratt’s approach to the subject, see

Information Transfer
Across Chu Spaces (pdf),
by Johan van Benthem
at the University of Amsterdam’s
Institute for Logic, Language,
and Computation

For a gloss on Sambin’s words
The image “http://www.log24.com/theory/images/SambinBP1-Diamondx.jpg” cannot be displayed, because it contains errors.
see the Log24 entry of Epiphany, 2005.