Authors:

Remember that not to be happy is not to be grateful.

Elizabeth Carter, Montagu Pennington (1807). “Memoirs of the Life of Mrs. Elizabeth Carter,: with a new edition of her poems, some of which have never appeared before; to which are added, some miscellaneous essays in prose, together with her notes on the Bible, and answers to objections concerning the Christian religion”, p.465
Remember that not to be happy is not to be grateful.