Excursus: the stipulatio Aquiliana

One of the most interesting illustrations of this combination of novatio and acceptilatio occurred in the case of the so-called stipulatio Aquiliana. Its formula had been composed by the Republican jurist Gaius Aquilius Gallus and read like this:

"[Q]uidquid te mihi ex quacumque causa dare facere oportet, oportebit...

It covered all debts, present and future, due and not yet owing, arising ex iure civili and under praetorian law, of the particular promisor against the stipulator and replaced them by a single comprehensive stipulation. Instead of many individual sums under various different kinds of obligations, only the grand total was now owed in terms of a contract verbis. This debt was then discharged by way of acceptilatio: "Quidquid tibi hodierno die per Aquilianam stipulationem spopondi, id omne habesne acceptum?" "Habeo acceptum." Ulpian describes what happened in the following words: "Aquiliana stipulatio omni­modo omnes praecedentes obligationes novat et peremit ipsaque peremitur per acceptilationem."^{[3875] [3876] What the parties achieved through this double transaction was a kind of general settlement. They had to go through, discuss and evaluate all claims of the stipulator against the promisor, as well as those counterclaims of the promisor against the stipulator that could be used for set-off purposes. If there turned out to be a balance in favour of the stipulator, the money was either paid back immediately, in which case the acceptilatio constituted a formal, general and comprehensive receipt, or the balance could again be credited to the promisor, usually by way of a further stipulation. This had to occur after conclusion of the acceptilatio, since otherwise the latter would automatically have covered—and thus discharged—the former. In both cases the acceptilatio had the effect of protecting the promisor against any further claims on the part of the stipulator that had their origin in a legal relationship predating the stipulatio Aquiliana. In other words, the promisor owed the stipulator either nothing at all (and could always refer to the acceptilatio in that regard) or only one single and specific sum that had to be spelt out and promised in a subsequent transaction.}

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