Never disregard what your enemies say. They may be severe, they may be prejudiced, they may be determined to see only in one direction, but still in that direction see clearly. They do not speak all the truth, but they generally speak the truth from one point of view; so far as that goes, attend to them.
The life of Benjamin Robert Haydon, from his autobiography and journals, ed. and compiled by T. Taylor (ed. 1853)