\begin{definition}[Definition:Predicate Logic]
'''Predicate logic''' is a sub-branch of symbolic logic.
It is an extension of propositional logic in which the internal structure of simple statements is analyzed.
Thus in '''predicate logic''', simple statements are no longer atomic.
The atoms of '''predicate logic''' are subjects and predicates of simple statements.
There are various formal systems allowing for rigid determination of the theorems of '''predicate logic''':
{{WIP|yes, and they are...?}}
{{expand|Explain that "predicate logic" is in fact a family of languages, so more accurate to call it ''a'' predicate logic.}}
\end{definition}