We learn (say) that Philip Larkin was most unadmirable in person, mean, sour, woman-despising, racist etc. And - since we unthinkingly embrace what C.S. Lewis called "the Personal Heresy", whereby the "Life" and the "Works" are "simply two diverse expressions of this single quiddity" - we can no longer admire and enjoy his poems (but for which no one would have written a biography of him, or edited his letters) because, despite what we may say to the contrary, we don't really believe that a bastard like that could write perfectly shaped, plangent lyrics. We should ask ourselves someone who wrote such poems could ever be such a bastard. Why don't we? Because we trust the biography or the letters more than the work, although the work comes from deep down in the man while the best biography in the world only scratches the surface.
D.J. Enright, Interplay: A Kind of Commonplace Book.