Don't bother checking someone's family background or whether they were ever bought and sold. If you hear them say 'Master' from the heart — even if they're a consul with all the ceremonial power — call them a slave. If you hear them say 'I'm miserable, look how much I suffer,' call them a slave. If you see them complaining, whining, and unhappy, call them a slave even if they wear the purple stripe of high office. But if they're not doing any of these things, don't assume they're free yet. Check their opinions first. Are their beliefs subject to pressure? Can they be blocked or ruined by bad luck? If so, call them a slave on vacation during Saturnalia — their master is just away for now. He'll be back soon, and then you'll see what they really go through.
And do not look, I entreat you, after his grandfathers and great-grandfathers, or inquire about his being bought or sold, but if you hear him saying from his heart and with feeling, "Master," even if the twelve fasces precede him (as consul), call him a slave. And if you hear him say, "Wretch that I am, how much I suffer," call him a slave. If, finally, you see him lamenting, complaining, unhappy, call him a slave, though he wears a praetexta. If, then, he is doing nothing of this kind do not yet say that he is free, but learn his opinions, whether they are subject to compulsion, or may produce hindrance, or to bad fortune, and if you find him such, call him a slave who has a holiday in the Saturnalia; say that his master is from home; he will return soon, and you will know what he suffers.