All the splendour of the highest prosperity can never enlighten the gloom with which so dreadful an idea must necessarily over-shadow the imagination; nor, in a wise and virtuous man, can all the sorrow of the most afflicting adversity ever dry up the joy which necessarily springs from the habitual and thorough conviction of the truth of the contrary system.
 Adam Smith, The Theory of Moral Sentiments (1759). copy citation

Context

“and who is determined, by his own unalterable perfections, to maintain in it at all times the greatest possible quantity of happiness.13 To this universal benevolence, on the contrary, the very suspicion of a fatherless world, must be the most melancholy of all reflections; from the thought that all the unknown regions of infinite and incomprehensible space may be filled with nothing but endless misery and wretchedness. All the splendour of the highest prosperity can never enlighten the gloom with which so dreadful an idea must necessarily over-shadow the imagination; nor, in a wise and virtuous man, can all the sorrow of the most afflicting adversity ever dry up the joy which necessarily springs from the habitual and thorough conviction of the truth of the contrary system. The wise and virtuous man is at all times willing that his own private interest should be sacrificed to the public interest of his own particular order or society. He is at all times willing, too, that the interest of this order or society should be sacrificed to the greater interest of the state or sovereignty, of which it is only a subordinate part.” source