=309.= The Stoic view of slavery can readily be inferred. Without proposing the immediate abolition of this social institution, the Stoics treated it as essentially contrary to nature[44]. The earliest teachers seem to have passed over the subject in silence; Panaetius (as might be expected from his social position), justified slavery by the arguments of Plato and Aristotle in exceptional cases: ‘all those who through the infirmity of their nature are unfit to govern themselves, are rightly made slaves’[45]. According to this theory we may speak of a ‘natural slave’ (φύσει δοῦλος), who as such can no more have rights in the community than the lower animals. The true Stoic theory appears however to be formulated by a definition of Chrysippus, who says that a slave is a ‘labourer hired for life[46].’ This definition makes of slavery a contract, to which there are two parties; and Seneca rightly uses this definition to argue that the relations of master to slave are those of man to man, and that as the master may wrong his slave, so the slave may do a service to his master[47]. All this is really implied in the dogma that ‘women and slaves may become philosophers,’ as is realized by the Church Father Lactantius[48]. [Sidenote: Constitutions.] =310.= The Stoic principles of politics may be realized under any form of government, and the theory of Constitutions, like that of grammar, belongs to a neutral ground on which philosophers of different schools may work in harmony. The Peripatetics appear first to have taken up this study; of the Stoics Diogenes of Babylon[49], who himself acted as a political representative of Athens, is stated to have shown interest in this subject; and after him Panaetius developed a complete theory, of which the substance is preserved for us in Cicero’s _de Re publica_[50]. According to this theory, which Cicero puts in the mouth of Scipio Africanus, surrounded by Roman Stoics of distinction such as Laelius, Tubero, and Furius Philo, the best constitution is one in which the elements of monarchy, aristocracy and democracy are combined, though a bias remains in favour of monarchy[51]. This mixed constitution, according to the teaching of Panaetius and his pupil Polybius, is best illustrated in the Roman state[52]; whereas tyranny, the perversion of monarchy, is the worst of all governments. By such reasoning the Roman nobles of the first century B.C. and the first century A.D. alike persuaded themselves easily that Stoic teaching supported the position of the republican party. But in fact they were maintaining Peripatetic theories of government, and the real Stoic theory was far more in accord with that practice of the principate, according to which all citizens are treated with respect, and the government of them is placed in the hands of men selected for their personal merit. We shall discuss the whole question of the relation of Stoicism to Roman politics in a later