Logic will get you from A to B. Imagination will take you everywhere.

## More theory …

After last post theoretical questions were open and the time for the writing was out. I will try to answer some of them now =)

## First order logic and Unification

First-order logic (FOL) or also called *predicate logic* has one or more arguments for each predicate and utilizes *quantifiers* (“for all” and “at least one”). First-order logic is simple but enough to formalize all classic mathematics. A first-order theorem, for example, consists in a set of axioms and sentences that we can reduce from them.

PROLOG is based on FOL and for that, in PROLOG one has the first-order unification algorithm implicit. *Unification* in logic is nothing more than an algorithmic process to solve systems of symbolic expressions. The solution of an *unification problem* is like a map of symbolic values for each variable in the system.