  Recently (arXiv:0910.2870), we have derived a fluctuation theorem for systems
in thermodynamic equilibrium compatible with anomalous response functions, e.g.
the existence of states with \textit{negative heat capacities} $C<0$. In this
work, we show that the present approach of the fluctuation theory introduces
new insights in the understanding of \textit{critical phenomena}. Specifically,
the new theorem predicts that the environmental influence can radically affect
critical behavior of systems, e.g. to provoke a suppression of the divergence
of correlation length $\xi$ and some of its associated phenomena as spontaneous
symmetry breaking. Our analysis reveals that while response functions and state
equations are \emph{intrinsic properties} for a given system, critical
behaviors are always \emph{relative phenomena}, that is, their existence
crucially depend on the underlying environmental influence.
