\begin{definition}[Definition:Frege Set Theory]
The '''Frege system of set theory''' is a system of axiomatic set theory which has as its sole axiom the comprehension principle:
{{:Axiom:Comprehension Principle}}
In support of this, the various logical axioms supporting predicate logic also hold.
It is accepted that the above statement lacks clarity, but the field of symbolic logic was less well understood when this system was first defined.
\end{definition}