women, but there were now two economic units in the marriage. Moreover, divorce could be initiated by either man or woman, often by saying "I divorce you" three times while in front of witnesses. The legal status of a mother as a citizen affected her son's citizenship. The phrase ex duobus civibus Romanis natos (“children born of two Roman citizens”) indicates that a Roman woman was regarded as having citizen status, in specific contrast to a peregrina. Slavery and freed men Slaves Slaves (servi) were not citizens, and lacked even the legal standing accorded free-born foreigners. Slaves were seen as property, and they were bought and sold like any other good in Rome. For the most part, slaves descended from debtors and from prisoners of war, especially women and children captured during sieges and other military campaigns in Greece, Italy, Spain, and Carthage. In the later years of the Republic and into the Empire, more slaves came from newly conquered areas of Gaul, Britain, North Africa, and Asia Minor. Many slaves were created as the result of Rome's conquest of Greece, but Greek culture was considered in some respects superior to that of Rome: hence Horace's famous remark Graecia capta ferum victorem cepit ("Captured Greece took her savage conqueror captive"). The Roman playwright Terence is thought to have been brought to Rome as a slave. Thus slavery was regarded as a circumstance of birth, misfortune, or war; it was defined in terms of legal status, or rather the lack thereof, and was neither limited to or defined by ethnicity or race, nor regarded as an inescapably permanent condition. Slavery was more prominent in Roman antiquity than anywhere else in the ancient world, save for Greece. Slaves who lacked skills or education performed agricultural or other forms of manual labor. More slaves were tasked with agricultural labour than any other form of work. Those who were violent or disobedient, or who for whatever reason were considered a danger to society, might be sentenced to labor in the mines, where they suffered under inhumane conditions. Slave owners were allowed to return their slaves for their money back if they were found to be defective, or if the seller had concealed anything that would affect the slave's productivity. Slaves that were found to be sick or defective would often be sold for very little, if anything. Masters would occasionally manumit sick or elderly