Circumstantia dicitur quod, extra substantiam actus existens, aliquo modo attingit ipsum, quia considerandum est in actibus quis fecit, quibus auxiliis vel instrumentis fecerit, quid fecerit, ubi fecerit, cur fecerit, quomodo fecerit, et quando fecerit.
A circumstance is described as something outside the substance of the act, and yet in a way touching it, because in acts we must take note of "who" did it, "by what aids" or "instruments" he did it, "what" he did, "where" he did it, "why" he did it, "how" and "when" he did it.
Tullius, in sua rhetorica, assignat septem circumstantias, quae hoc versu continentur, "quis, quid, ubi, quibus auxiliis, cur, quomodo, quando".
Tully, in his Rhetoric (De Invent. Rhetor. i), gives seven circumstances, which are contained in this verse: "who, what, where, by what aids, why, how, and when".
Sed Aristoteles, in III Ethic., addit aliam, scilicet circa quid, quae a Tullio comprehenditur sub quid.
But Aristotle in Ethic. iii, 1 adds yet another, to wit, "about what", which Tully includes in the circumstance "what".
Contingit autem hoc fieri tripliciter, uno modo, inquantum attingit ipsum actum; alio modo, inquantum attingit causam actus; tertio modo, inquantum attingit effectum.
Ipsum autem actum attingit, vel per modum mensurae, sicut tempus et locus;
vel per modum qualitatis actus, sicut modus agendi.
Ex parte autem effectus, ut cum consideratur quid aliquis fecerit.
Ex parte vero causae actus, quantum ad causam finalem, accipitur propter quid;
ex parte autem causae materialis, sive obiecti, accipitur circa quid;
ex parte vero causae agentis principalis, accipitur quis egerit;
ex parte vero causae agentis instrumentalis, accipitur quibus auxiliis.
Now this happens in three ways: first, inasmuch as it touches the act itself; secondly, inasmuch as it touches the cause of the act; thirdly, inasmuch as it touches the effect.
It touches the act itself, either by way of measure, as "time" and "place";
or by qualifying the act as the "mode of acting."
It touches the effect when we consider "what" is done.
It touches the cause of the act, as to the final cause, by the circumstance "why";
as to the material cause, or object, in the circumstance "about what";
as to the principal efficient cause, in the circumstance "who";
and as to the instrumental efficient cause, in the circumstance "by what aids",