If you are in doubt whether to write a letter or not, don't. And the advice applies to many doubts in life besides that of letter writing.
Edward Bulwer-Lytton, 1st Baron LyttonAt court one becomes a sort of human ant eater, and learns to catch one's prey by one's tongue.
Edward Bulwer-Lytton, 1st Baron LyttonHe that fancies himself very enlightened, because he sees the deficiencies of others, may be very ignorant, because he has not studied his own.
Edward Bulwer-Lytton, 1st Baron Lytton