Book 3.31
No man is satisfied with his own lot if he fixes his attention on that of another: and this leads to our being angry even with the gods, because somebody precedes us, though we forget of how many we take precedence, and that when a man envies few people, he must be followed in the background by a huge crowd of people who envy him. Yet so churlish is human nature, that, however much men may have received, they think themselves wronged if they are able to receive still more. "He gave me the praetorship. Yes, but I had hoped for the consulship. He bestowed the twelve axes upon me: true, but he did not make me a regular consul. He allowed me to give my name to the year, but he did not help me to the priesthood. I have been elected a member of the college: but why only of one? He has bestowed upon me every honour that the state affords: yes, but he has added nothing to my private fortune. What he gave me he was obliged to give to somebody: he brought out nothing from his own pocket." Rather than speak thus, thank him for what you have received: wait for the rest, and be thankful that you are not yet too full to contain more: there is a pleasure in having something left to hope for. Are you preferred to everyone? then rejoice at holding the first place in the thoughts of your friend. Or are many others preferred before you? then think how many more are below you than there are above you. Do you ask, what is your greatest fault? It is, that you keep your accounts wrongly: you set a high value upon what you give, and a low one upon what you receive.