That's metaphysics, my dear fellow. It's forbidden me by my doctor, my stomach won't take it.
Source: Ivan Ivanovich, in Doctor Zhivago, ch. 1, sct. 5 (1957).
-- Boris Pasternak, (Feb 10 1890-1960), Russian novelist, poet; His novel Doctor Zhivago helped win him the Nobel Prize for Literature, 1958 but aroused so much opposition at home that he declined the honor.