$\forall$$T$:Type, $Q$, $R$, $S$:($T$$\rightarrow$$T$$\rightarrow\mathbb{P}$). ($Q$ $\equiv>$\{$T$\} $R$) $\Rightarrow$ ($R$ $\equiv>$\{$T$\} $S$) $\Rightarrow$ ($Q$ $\equiv>$\{$T$\} $S$)