For decades, John Sowa has been one of the leading lights in the discipline of Knowledge Representation. This document collects notes on his work.
Symbolic logic has two main branches: propositional logic and predicate logic.
Propositional logic treats propositions as single units. (p -> “Trailer trucks have 18 wheels.”)
Predicate logic analyzes propositions into combinations of predicates. (trailerTruck(x) and wheel(x) are examples of predicates)
A predicate or relation is a function that maps its arguments to the truth values 1/0 or T/F.
Less than (<) is a good example of a predicate.
(< 5 12) => T (< 12 5) => F
Sowa’s Ontology is described in detail in his book Knowledge Representation. Page 72 presents the top three distinctions in lattice form.
The three distinctions are:
- I/R/M (Independent/Relative/Mediating)
- P/A (Physical/Abstract)
- C/O (Continuant/Occurrent)
Combinations of distinctions:
- IP (Actuality)
- IA (Form)
- RP (Prehension)
- RA (Proposition)
- MP (Nexus)
- MA (Intention)
Three letter concepts
- IPC (Object)
- IPO (Process)
- IAC (Schema)
- IAO (Script)
- RPC (Juncture)
- RPO (Participation)
- RAC (Description)
- RAO (History)
- MPC (Structure)
- MPO (Situation)
- MAC (Reason)
- MAO (Purpose)
The purpose of the ontology is to provide a framework of distinctions that can be used to discriminate and classify the things that exist and define the words that describe them.
But no fixed collection of distinctions or categories is likely to be adequate for describing all things for all time.