([b.]) suōs quisque opprimī nōn patitur, neque, aliter sī faciat, ūllam inter suōs habet auctōritātem, 6, 11, 4, nobody suffers his vassals to be put down, and if he ever act otherwise, he has no influence among his people. laeduntur artēriae, sī ācrī clāmōre compleantur, Cornif. 3, 21, it always hurts the windpipe, if it be filled out with a sharp scream. turpis excūsātiō est, sī quis contrā rem pūblicam sē amīcī causā fēcisse fateātur, L. 40, it is always a discreditable apology, if a man confess that he has been unpatriotic from motives of friendship. Britannī iniūncta imperiī mūnera impigrē obeunt, sī iniūriae absint, Ta. Agr. 13, the Britons are always perfectly ready to perform the duties enjoined on them by the Roman government, if they be not maltreated.
[2071.] (2.) The imperfect or pluperfect subjunctive is sometimes used in general past suppositions ([1730]).
This use begins with Catullus and Caesar, the indicative being the regular classical construction ([2044], [2050]).
chommoda dīcēbat, sī quandō commoda vellet dīcere Arrius, Cat. 84, 1, hadvantages said Arrius, if advantages he ever meant to say. sī quis prehenderētur, cōnsēnsū mīlitum ēripiēbātur, Caes. C. 3, 110, 4, every time a man was taken up, he was rescued by the joint action of the rank and file. sīn autem locum tenēre vellent, nec virtūtī locus relinquēbātur, neque coniecta tēla vītāre poterant, 5, 35, 4, but if on the other hand they undertook to hold their position, there was never any opening for bravery, nor could they ever dodge the shower of missiles. sīn Numidae propius accessissent, ibī̆ virtūtem ostendere, S. I. 58, 3, they showed forth their valour every time the Numidians drew near ([1535]).
[2072.] The present or perfect subjunctive may be used in a conditional protasis of future time.
[2073.] The apodosis is usually in the present subjunctive, less frequently in the perfect subjunctive. The imperfect and pluperfect subjunctive are rare ([2089]).
[2074.] The indicative is sometimes used in the apodosis, especially in expressions of ability, duty, &c. ([1495]); nōn possum is regularly in the indicative when the protasis is also negative. For the future indicative the periphrastic form is sometimes used.
[2075.] In the early period, before the imperfect subjunctive had been shifted to denote present time in conditional sentences ([2091]), the present subjunctive was used to express action non-occurrent in present time. Examples of this use are found in Plautus: as, sī honestē cēnseam tē facere posse, suādeam; vērum nōn potest; cave faxīs, Pl. MG. 1371, if I thought that you could do the thing with credit to yourself, I should advise you to; but ’tis impossible; so don’t you do it. vocem tē ad cēnam, nisi egomet cēnem forīs, Pl. St. 190, I should ask you home to dine, if I were not dining out myself. Such sentences must not be confused with those in which an action from the nature of things impossible is represented as of possible occurrence.