$\forall$$T$:Type, $R$, $R_{2}$:($T$$\rightarrow$$T$$\rightarrow\mathbb{P}$).
\\[0ex]Trans($T$;$1$,$2$.$R_{2}$($1$,$2$)) $\Rightarrow$ ($\forall$$x$, $y$:$T$. ($x$ $R$ $y$) $\Rightarrow$ ($x$ $R_{2}$ $y$)) $\Rightarrow$ ($\forall$$x$, $y$:$T$. ($x$ $R$\^{}+ $y$) $\Rightarrow$ ($x$ $R_{2}$ $y$))