from Wiktionary, Creative Commons Attribution/Share-Alike License.
- adjective Not
from Wiktionary, Creative Commons Attribution/Share-Alike License
In his 1919 paper he established some results for lattices, in particular, he showed that one could decide the validity of universal Horn sentences (i. e, universal sentences with a matrix that is a disjunction of negated and unnegated atoms, with at most one positive atom) by a procedure that we now recognize to be a polynomial time algorithm.
They are conjunctions of complete descriptions of each individual, each description itself a conjunction containing exactly one occurrence (negated or unnegated) of each predicate of the language.