MAYBE Proof: ConCon could not decide confluence of the system. \cite{SMI95}, Corollary 4.7 or 5.3 do not apply. Some critical pairs are not trivial and ConCon could not decide whether those all are infeasible. tp2($7, cons($6, y)) = tp2(cons($6, x), $3) <= split($5, $8) = tp2(x, $3), le($5, $6) = false, split($5, $8) = tp2($7, y), le($5, $6) = true: For all conditions c 'tcap(c.lhs)' is unifiable with c.rhs.