Subjunctive Conditions
Two conditions that use the subjunctive indicate actions that would have happened upon the enactment of some condition; however, that condition was not met, so the entire condition is just a thought experiment that is contrary to what factually happened or is happening. A third condition that uses the subjunctive indicates an action that may occur in the future contingent upon the completion of a condition, but it’s uncertain whether it will happen.
Past Contrary-to-Fact
A past contrary-to-fact (or past contrafactual) condition indicates what would have happened if something had happened. Both clauses will use the pluperfect subjunctive.
The protasis will translate the pluperfect subjunctive straightforwardly: “had [verb]ed”.
The apodosis will translate the pluperfect subjunctive with the auxiliaries “would have [verb]ed.”
- sī id fēcisset, sapiēns fuisset. If he had done it, he would have been wise.
Note that the subjunctive mood indicates the irreality of this condition. If he had done it, he would have been wise: but he didn’t do it, and therefore he wasn’t. The condition is contrary to fact because it didn’t happen.
Present Contrary-to-Fact
A present contrary-to-fact (or present contrafactual) condition indicates what would happen if something were happening. Both clauses will use the imperfect subjunctive.
The protasis will translate the imperfect subjunctive with the auxiliary “were [verb]ing.”
The apodosis will translate the imperfect subjunctive with the auxiliary “would [verb].”
- sī id faceret, sapiēns esset. If he were doing it, he would be wise.
The same contrary-to-fact-ness applies to this condition, but in present time. If he were doing it, he would be wise – but he isn’t doing it, and so he’s not.
Future Less Vivid
The future less vivid condition indicates an action that would happen in the future, if another action should happen first. Both clauses will use the present subjunctive.
The protasis will translate the present subjunctive with the auxiliary “should [verb].”
The apodosis will translate the present subjunctive with the auxiliary “would [verb].”
- sī id faciat, sapiēns sit. If he should do it, he would be wise.
Note that the translation of the apodosis is the same as the apodosis of a present contrary-to-fact; the difference lies in the time when the action of the protasis would be completed: in the present for a present contrary-to-fact; in the future for a future less vivid.
Rarely, you may see a perfect subjunctive instead of a present subjunctive in the protasis:
- sī id fēcerit, sapiēns sit. If he should do it, he would be wise.
Be careful not to mix up the future less vivid, a subjunctive condition that uses the present subjunctive, with the future more vivid, an indicative condition that uses the future or future perfect indicative. The future more vivid is “more vivid” because of the indicative mood, indicating that it’s likely to happen; the future less vivid is “less vivid” because the subjunctive mood introduces a note of doubt.