Termination of the given GTRS could not be shown:

(0) Obligation:

Generalized rewrite system (where rules with free variables on rhs are allowed):
The TRS R consists of the following rules:

and(tt) → X
__(__(X, Y), Z) → __(X, __(Y, Z))
__(X, nil) → X
__(nil, X) → X
isList → isNeList
isList → tt
isList → and(isList)
isNeList → isQid
isNeList → and(isList)
isNeList → and(isNeList)
isNePal → isQid
isNePal → and(isQid)
isPal → isNePal
isPal → tt
isQid → tt