{\hbox{\normalsize$\forall$}}%
{\hbox{\scriptsize$\forall$}}}%
}
+\newcommand{\bigexists}{%
+ \mathop{\mathchoice%
+ {\hbox{\huge$\exists$}}%
+ {\hbox{\Large$\exists$}}%
+ {\hbox{\normalsize$\exists$}}%
+ {\hbox{\scriptsize$\exists$}}}%
+}
\newcommand{\Largeexists}{\mathop{\hbox{\Large$\exists$}}}
\newcommand{\Largenexists}{\mathop{\hbox{\Large$\nexists$}}}