Institutio Oratoria

I should imagine that there could never be a case, or at any rate an actual case in the courts, in which neither side said anything about the character of the persons involved; but this is not true of causes and motives, for it is often wholly unnecessary to trouble ourselves about them, as, for example, in cases of theft or adultery, crimes which carry their motives on the face of them.

Next we must consider the intention, a term which involves a number of questions, such as whether it is probable that the accused hoped that he would be able to carry such a crime into effect, or that it would escape detection when committed, or that, even if detected, it would be pardoned or punished but lightly or after considerable lapse of time, or that the inconvenience involved by the penalty would be outweighed by the pleasure resulting from the crime: or again, whether it was worth while incurring the penalty;