$\forall$$T$:Type, $R$:($T$$\rightarrow$$T$$\rightarrow$prop\{i:l\}), $x$,$y$,$z$:$T$.
\\[0ex]($x$ rel\_star($T$; $R$) $y$) $\Rightarrow$ ($y$ rel\_star($T$; $R$) $z$) $\Rightarrow$ ($x$ rel\_star($T$; $R$) $z$)