Ross Feld has quoted Philip Guston, from an essay in which the great painter wrote, "I do not see why a loss of faith in the known image and symbol in our time should be celebrated as a freedom. It is a loss from which we suffer, and this pathos motivates modern painting and poetry at its heart."
Guston wrote this while painting in an abstract mode, and the quote demonstrates why Guston's willingness to be self-critical allowed him to maintain a lifelong independence from theoretical blind alleys. Eugene Victor Thaw referred to Guston's relationship to Abstract Expressionism as a "friendly proximity."
What interests me is that Guston acknowledged loss and its resulting grief, in a way that must not have been popular at the time and that gains credibility in retrospect.