When we consult only our own policy, and attempt to find a nearer way to good by over-leaping the settled boundaries of right and wrong, we cannot be happy even by success, because we cannot escape the consciousness of our fault
 Samuel Johnson, The History of Rasselas, Prince of Abissinia (1759). copy citation

Context

“Man cannot so far know the connection of causes and events as that he may venture to do wrong in order to do right. When we pursue our end by lawful means, we may always console our miscarriage by the hope of future recompense. When we consult only our own policy, and attempt to find a nearer way to good by over-leaping the settled boundaries of right and wrong, we cannot be happy even by success, because we cannot escape the consciousness of our fault; but if we miscarry, the disappointment is irremediably embittered. How comfortless is the sorrow of him who feels at once the pangs of guilt and the vexation of calamity which guilt has brought upon him!” source