They extended the proprietarial and contractual provisions of emerging commercial law to seize local peasant debtors as slaves, … ‘Proprietarial’ interests in both outsiders and local debtors, commercialized for purposes of negotiability, thus appeared several millennia ago in Mesopotamia. However, to construe these atypical transactions … as defining of ‘slavery’, would then indulge the selective fallacy of origins — in relation to modern thoroughly proprietarial slavery …