Logic Engines

• "simple" - prolog-like engine with some simple 2nd order infon logic support. linear but incomplete.
• based on Propositional Primal Infon Logic (complexity in propositional case):
  • BPIL = Basic Primal Infon Logic. Linear.
  • SPIL = BPIL + Conjunctions as sets. Implementations:
    • SPIL - randomized algorithm. Linear on average for all inputs. (SPILrnd)
    • SPILsufarr - deterministic algorithm based on suffix arrays. O(depth*length) worst case time complexity.
    • SPILhash - deterministic algorithm based on hashing. Linear on average.
  • TPIL - BPIL + transitive rule. Quadratic time complexity.
  • TSPIL - SPIL + transitive tule. Cubic time complexity.
• UFOL - allows for expressions in the universal fragment of first order logic. Negation and disjunction are allowed, but be aware that failure to infer a given formula is not equivalent to ability to infer its negation. In the same tone, ability to infer a disjunction is not equivalent to ability to infer any of its disjuncts.
• datalog - the datalog engine takes advantage of Propositional Primal Infon Logic translation to Datalog, and it employs Z3's datalog solver as backend.