In this notorious chapter Aristotle describes, from his own teleological standpoint, the position of the slave in his day. According to him, the slave is a ‘live tool’ used by the master for purposes of ‘life’ and ‘action’, not of production. He is of course thinking of the household, which is not primarily productive; but even so it looks as if his bias in favour of a ‘gentlemanly’ life has tempted him into thinking of a slave as invariably in personal attendance on his master. In fact, many slaves were used in productive labour in factories and mines and on farms.
In the third paragraph of the chapter, the argument seems to be: (a) a piece of property is described in the same terms as a part; (b) a part ‘belongs to another tout court’ (i.e. to the whole); (c) slaves are pieces of property; so (d) slaves ‘belong to others tout court’ (i.e. to their masters) – whereas masters, not being pieces of property, are master ‘of’ their slaves but do not ‘belong to them tout court’.
Is Aristotle suggesting that the slave ‘belongs tout court’ to his master in the sense of being dependent on him as a member of a ‘pair’, or perhaps in the way an individual is ‘part’ of the state (I ii)? If so, the naturalness of the ‘belonging’ is in a sense established. But the implications of the argument are none too lucid, and evidently it is in Chapters v–vii that the main arguments for the naturalness of slavery are presented.
1253b23 Now property is part of a household, and the acquisition of property part of household-management; for neither life itself nor the good life is possible without a certain minimum supply of the necessities. Again, in any special skill the availability of the proper tools will be essential for the performance of the task; and the household-manager must have his likewise. Tools may be animate as well as inanimate; for instance, a ship’s captain uses a lifeless rudder, but a living man for watch; for a servant is, from the point of view of his craft, categorized as one of its tools. So any piece of property can be regarded as a tool enabling a man to live, and his property is an assemblage of such tools; a slave is a sort of living piece of property; and like any other servant is a tool in charge of other tools. For suppose that every tool we had could perform its task, either at our bidding or itself perceiving the need, and if – like the statues made by Daedalus or the tripods of Hephaestus, of which the poet says that ‘self-moved they enter the assembly of the gods’1 – shuttles in a loom could fly to and fro and a plucker2 play a lyre of their own accord, then master-craftsmen would have no need of servants nor masters of slaves.
1254a1 Tools in the ordinary sense are productive tools, whereas a piece of property is meant for action.3 I mean, for example, a shuttle produces something other than its own use, a bed or a garment does not. Moreover, since production and action differ in kind and both require tools, the difference between their tools too must be of the same kind. Now life is action and not production; therefore the slave, a servant, is one of the tools that minister to action.
1254a9 A piece of property is spoken of in the same way as a part is; for a part is not only part of something but belongs to it tout court; and so too does a piece of property. So a slave is not only his master’s slave but belongs to him tout court, while the master is his slave’s master but does not belong to him. These considerations will have shown what the nature and functions of the slave are: any human being that by nature belongs not to himself but to another is by nature a slave; and a human being belongs to another whenever, in spite of being a man, he is a piece of property, i.e. a tool having a separate existence4 and meant for action.3