Records of slavery in Ancient Greece go as far back as Mycenaean Greece. The origins are not known, but it appears that slavery became an important part of the economy and society only after the establishment of cities. Slavery was common practice and an integral component of ancient Greece, as it was in other societies of the time, including ancient Israel. It is estimated that in Athens, the majority of citizens owned at least one slave. Most ancient writers considered slavery not only natural but necessary, but some isolated debate began to appear, notably in Socratic dialogues. The Stoics produced the first condemnation of slavery recorded in history.