But Scaevola, the son of Publius Scaeaevola, thinks the word is a compound one, so that it is made up of post and limen.  So that those things which have been alienated from us, when they have come into the possession of our enemies, and, as it were, departed from their own threshold, then when they have returned behind that same threshold, appear to have returned postliminio.  By which definition even the cause of Mancinus may be defended by saying that he returned postliminio,—­that he was not surrendered, inasmuch as he was not received.  For that no surrender and no gift can be understood to have taken place if there has been no reception of it.

IX.  We next come to that topic which is derived from those things which are disposed in some way or other to that thing which is the subject of discussion.  And I said just now that it was divided into many parts.  And the first topic is derived from combination, which the Greeks call [Greek:  sizugia], being a kindred thing to observation, which we have just been discussing, as, if we were only to understand that to be rain-water which we saw to have been collected from rain, Mucius would come, who, because the words pluna and pluendo were akin, would say that all water ought to be kept out which had been increased by raining.  But when an argument is derived from a genus, then it will not be necessary to trace it back to its origin, we may often stop on this side of that point, provided that which is deduced is higher than that for which it is deduced, as, “Rain water in its ultimate genus is that which descends from heaven and is increased by showers,” but in reference to its more proximate sense, under which the right of keeping it off is comprised, the genus is, mischievous rain water.  The subordinate species of that genus are waters which injure through a natural defect of the place, or those which are injurious on account of the works of man:  for one of these kinds may be restrained by an arbitrator, but not the other.

Again, this argumentation is handled very advantageously, which is derived from a species when you pursue all the separate parts by tracing them back to the whole, in this way “If that is dolus malus when one thing is aimed at, and another pretended,” we may enumerate the different modes in which that can be done, and then under some one of them we may range that which we are trying to prove has been done dolo malo.  And that kind of argument is usually accounted one of the most irrefragable of all.

X. The next thing is similarity, which is a very extensive topic, but one more useful for orators and for philosophers than for men of your profession.  For although all topics belong to every kind of discussion, so as to supply arguments for each, still they occurs more abundantly in discussions on some subjects, and more sparingly in others.  Therefore the genera are known to you, but when you are to employ them