but no man is so brave that he may not meet such defeats and disasters as to discourage him and dampen his ardor for any cause, no matter how just he deems it.
 Ulysses S. Grant, Personal Memoirs of Ulysses S. Grant (1885). copy citation

Context

“Johnston's army was demoralized by constant defeat and would hardly have made an offensive movement, even if they could have been induced to remain on duty. The men of both Lee's and Johnston's armies were, like their brethren of the North, as brave as men can be; but no man is so brave that he may not meet such defeats and disasters as to discourage him and dampen his ardor for any cause, no matter how just he deems it. CHAPTER LXIII. ARRIVAL OF THE PEACE COMMISSIONERS—LINCOLN AND THE PEACE COMMISSIONERS—AN ANECDOTE OF LINCOLN—THE WINTER BEFORE PETERSBURG—SHERIDAN DESTROYS THE RAILROAD—GORDON CARRIES THE PICKET LINE—PARKE RECAPTURES THE LINE—THE LINE OF BATTLE OF WHITE OAK ROAD.” source