Translate the following inference to logic notation: For all x, if x_5 drinks water, then x_5 is a doctor. For all x, x_5 is not a doctor. For all x, x_5 is a taxi driver if and only if x_5 will read a book. For all x, x_5 will drink water if and only if x_5 will read a book. Therefore for all x, x_5 is not a taxi driver.
forall x: P(x) -> Q(x). forall x: ~Q(x). forall x: R(x) <-> S(x). forall x: P(x) <-> S(x). Therefore forall x: ~R(x).