Vivid knowledge

Vivid knowledge refers to a specific kind of knowledge representation.

The idea of a vivid knowledge base is to get an interpretation mostly straightforward out of it – it implies the interpretation. Thus, any query to such a knowledge base can be reduced to a database-like query.

Propositional knowledge base

A propositional knowledge base KB is vivid iff KB is a complete and consistent set of literals (over some vocabulary).

Such a knowledge base has the property that it as exactly one interpretation, i.e. the interpretation is unique. A check for entailment of a sentence can simply be broken down into its literals and those can be answered by a simple database-like check of KB.

First-order knowledge base

A first-order knowledge base KB is vivid iff for some finite set of positive function-free ground literals KB⁺,

KB = KB⁺ ∪ Negations ∪ DomainClosure ∪ UniqueNames,

whereby

Negations ≔ { ¬p | p is atomic and KB ⊭ p },

DomainClosure ≔ { (c_i ≠ c_j) | c_i, c_j are distinct constants },

UniqueNames ≔ { ∀x: (x = c₁) ∨ (x = c₂) ∨ ..., where the c_i are all the constants in KB⁺ }.

All interpretations of a vivid first-order knowledge base are isomorphic.

See also

• Closed world assumption