Quintilian, Institutio Oratoria, Book 7
Harold Edgeworth Butler, Ed.

[27] For the opponent will say that the person in question is actually serving as a slave or is legally in a state of servitude. We must therefore look for properties and differences, to which in passing I devoted a brief discussion in my fifth book.¹ A slave when manumitted becomes a freedman: a man who is assigned for debt becomes a free man on the restoration of his liberty. A slave cannot acquire his freedom without the consent of his master: a man assigned for debt can acquire it by paying his debt without the consent of his master being necessary. A slave is outside the law; a man assigned for debt is under the law. Turning to properties, we may note the following which are possessed by none save the free, the three names (praenomen, nomen and cognomen) and membership of a tribe, all of which are possessed by the man assigned for debt.