The tragedy of life is not so much what men suffer, but rather what they miss.

Thomas Carlyle (1795–1881) Scottish essayist and historian

(Attributed)

This phrase is widely attributed to Carlyle, but without any actual citation to his works I could find. The earliest ascription to Carlyle of this phrase seems to be in Fulton Sheen, Peace of Soul, ch. 13 (1949); given the popularity of Sheen's book, if he misquoted and/or misattributed the quotation to Carlyle, the error may have stuck.

It's (also, additionally) possible that this phrase was slightly changed and re-attributed from the words of Engish writer John Ruskin (1819-1900), who considered Carlyle a mentor: "I wonder not so much at what people suffer as what they lose." While, again, I cannot find a primary source for that, it is attributed to Ruskin in Arthur Winnington, A Mission of the Spirit (1906) and in the literary journal The Dial, Vol. 59, No. 706 (1915-11-25).