At the base of Rome's peculium economy

Why did Roman slaves have a peculium or purse? It has been suggested that the grant of a peculium was a clever arrangement, a trick actually, by means of which owners incentivised slaves to perform unsupervised labour. Upon this incentive base stands Rome's "peculium economy" in which diverse and far-flung business and other activities are performed by minimally supervised slaves. However, forcibly taken slaves (including born-slaves), the kind still taken for granted in the scholarly literature, would not be sufficiently incentivised by peculia. The "peculium economy" stands, however, because the slaves forming its base are slaves by contract/self-sellers. The peculium, the legal and other evidence suggests, is a contractual benefit desired by and typically made available to free individuals who volunteered for slavery. This is precisely how, for example, the "peculium" arose in the eighteenth century trade in "indentured servants" between England and North America. The paper explores this finding and develops its implications for Roman economic growth.