$\forall$${\it es}$:ES, $p$:(E$\rightarrow$(E + Top)).
\\[0ex]causal{-}predecessor(${\it es}$;$p$)
\\[0ex]$\Rightarrow$ ($\forall$$a$, $b$, $c$:E. same{-}thread(${\it es}$;$p$;$a$;$b$) $\Rightarrow$ same{-}thread(${\it es}$;$p$;$b$;$c$) $\Rightarrow$ same{-}thread(${\it es}$;$p$;$a$;$c$))