 ""St Thomas Aquinas in mid-thirteenth century accepted the new Aristotelian view of slavery as well as the titles of slave ownership derived from Roman civil law, and attempted - without complete success - to reconcile them with Christian patristic tradition.He takes the patristic theme... that slavery exists is a consequence of original sin and says that it exists according to the "second intention" of nature; it would not have existed in the state of original innocence according to the "first intention" of nature; in this way he can explain the Aristotelian teaching that some people are slaves "by nature" like inanimate instruments, because of their personal sins; for since the slave cannot work for his own benefit slavery is necessarily a punishment.He accepts the symbiotic master-slave relationship as being mutually beneficial.