REPRESENTAÇÃO DO CONHECIMENTO
Terças – 13 hs – sala 512 RDC
Definition: The study of propositions and their use in argumentation.
Major task: establish a systematic way of deducing the logical consequences of a set of sentences.
EnciclopÆdia Britannica.
Logic
Lógica Matemática
Leibniz Reduce reasoning to mathematical
computation
Corpo = substância material = 2x3=6
Humano = 2x3x7x13x19= 10.374
Divide por 6 =>Humano é corpo
Não divide por 66(mineral) => Humano não é mineral
T-Box & A-Box
Brachman et al. T-box – term definition A-box – assertion definition lattices
Álgebra Booleana
0 – false 1 – truth
Conjunction X – and Disjunction + - or Negation – not
Truth Tables
Portas Lógicas
Frege’s Begriffsschrift
Peirce
Σ – repeated or (logical sum) Π – repeated and (logical product)
Peano
Propositional Logic
Every trailer truck has 18 wheels.
Propositional Logic
Every trailer truck has 18 wheels. => p
Syllogism
Predicate and Subject
Predicate Logic
Universal with implication Existential with conjuction
Logic and Ontology
Harder to read Distracting detail from the variables – used to
link parts of the formula Logic is simple – half a dozen symbols. Level
of detail depends on the predicates that do not belong to logic. They represent an ontology of relevant things in
the domain. Choices represent ontological commitments.
Predicates in an ontology Domain dependent Domain independent
Varieties of Logic
Syntax Subsets
description logics Proof theory Model theory Ontology
Uninterpreted logic: bunch of symbols, quatifiers, operators
Set theory for Math Metalanguage
Typed Logic
Notational engineering Avoids extra implications that accompany the universal quantifier
Lambda Calculus
Church notation for defining functions and a method for convertingany given definition into other equivalent definitions
Conceptual Graphs
System of logic Based on
Existential graphs by Peirce Semantic Networks
A cat is on the Mat Every cat is on a mat
KIF
Knowledge Interchange Format Version of typed predicate logic –
Genesereth, Fikes et al.
KIF
Knowledge Interchange Format Version of typed predicate logic –
Genesereth, Fikes et al.
A cat is on the Mat Every cat is on a mat
Logic
Vocabulary Domain independent logical symbols Constants: individuals, properties, relations Variables Punctuation
Syntax Semantics Rules of inference
Top Related