"nothing is so hard as man s ingratitude" in German Nothing is so hard as man's ingratitude. Undank ist der Welt Lohn. Undank ist der Welten Lohn. Detailed translations for "nothing is so hard as man s ingratitude" Nothing is so hard as man's ingratitude. Nothing is so hard as man's ingratitude. Undank ist der Welt Lohn. Nothing is so hard as man's ingratitude. Undank ist der Welten Lohn.