Barwise is able to prove the nonequivalence between the fixed point and the hierarchical account he claims.    From Wordnik.com.  [Common Knowledge] Reference

The above definition of T has made their nonequivalence quite clear.    From Wordnik.com.  [iMechanica - Comments] Reference

Two facts contribute to an extraordinary importance and, at the first glance, a strange use of transparent nodes: the invisibility of nodes, and the nonequivalence of the object's area and its cover's area.    From Wordnik.com.  [The Code Project Latest Articles] Reference