On the other hand, contracts between private persons under ordinary circumstances gave no claim for legal aid on the part of the state.

The only protection of the creditor was the debtor's word of honour which was held in high esteem after the wont of merchants, and possibly also, in those frequent cases where an oath had been added, the fear of the gods who avenged perjury.
The only contracts legally actionable were those of betrothal (the effect of which was that the father, in the event of his failing to give the promised bride, had to furnish satisfaction and compensation), of purchase (-mancipatio-), and of loan (-nexum-).
A purchase was held to be legally concluded when the seller delivered the article purchased into the hand of the buyer (-mancipare-) and the buyer at the same time paid to the seller the stipulated price in presence of witnesses.

This was done, after copper superseded sheep and cattle as the regular standard of value, by weighing out the stipulated quantity of copper in a balance adjusted by a neutral person.( 4) These conditions having been complied with, the seller had to answer for his being the owner, and in addition seller and purchaser had to fulfil every stipulation specially agreed on; the party failing to do so made reparation to the other, just as if he had deprived him of the article in question.

But a purchase only founded an action in the event of its being a transaction for ready money: a purchase on credit neither gave nor took away the right of property, and constituted no ground of action.

A loan was negotiated in a similar way; the creditor weighed over to the debtor in presence of witnesses the stipulated quantity of copper under the obligation (-nexum-) of repayment.