Source : Free On-Line Dictionary of Computing

Axiom of Comprehension
     
         An {axiom schema} of {set theory} which states:
        if P(x) is a {property} then
     
        	{x : P}
     
        is a set.  I.e. all the things with some property form a set.
     
        Acceptance of this axiom leads to {Russell's Paradox} which is
        why {Zermelo set theory} replaces it with a restricted form.
     
        (1995-03-31)