$\forall$$a$:Id, $T$:Type, ${\it ds}$:$x$:Id fp$\rightarrow$ Type, $P$:(State(${\it ds}$)$\rightarrow$$T$$\rightarrow$Prop), ${\it init}$:$x$:Id fp$\rightarrow$ ${\it ds}$($x$)?Void. \\[0ex]$T$ \\[0ex]$\Rightarrow$ AtomFree(Type;$T$) \\[0ex]$\Rightarrow$ $\forall$$x$$\in$dom(${\it ds}$). $A$=${\it ds}$($x$) $\Rightarrow$ $A$ \\[0ex]$\Rightarrow$ $\forall$$x$$\in$dom(${\it ds}$). $A$=${\it ds}$($x$) $\Rightarrow$ AtomFree(Type;$A$) \\[0ex]$\Rightarrow$ ($\forall$$s$:State(${\it ds}$). Dec($\exists$$v$:$T$. $P$($s$,$v$))) \\[0ex]$\Rightarrow$ Feasible(with ds: ${\it ds}$ init: ${\it init}$action $a$:$T$ precondition $a$(v) is $P$)