Conditions ch. 44

In both Latin and English there are two main kinds of conditions. Simple or general conditions that use regular indicative verbs and ideal or imaginary conditions that use subjunctive verbs.

SIMPLE/GENERAL CONDITIONS

Simple conditions are constructed in the same way in English and Latin for present and past tenses. In Latin si = if and nisi = unless/if not. In general conditions, the verbs are still indicative, but we may translate "if ever" or "whenever", in Latin as in English a word like umquam (ever) may occur in the if-clause, and a word like semper (always) or saepe (often) may occur in the then-clause of a general condition.

Examples:
If he left, I followed. {Past general = Whenever he left, I followed.
Si discessit, secutus sum.
If you are coming, we are coming too.
Si venis, quoque venimus.
Unless he is leaving, we are not staying.
Nisi discedit, non manemus.

However, future or future perfect simple conditions (which are also called future more vivid conditions) have a present or perfect tense verb in the if-clause in English while Latin follows the logical sequence and uses future or future perfect tense for both clauses.

Examples:
If they come, I will see them.
Si venient(fut.)/venerint(fut. perf.), eos videbo(fut.).
If you build it, they will come.
Si id aedificabis(fut.)/aedificaveris(fut. perf.), venient(fut.).
Unless you remind them, they won't remember.
Nisi eos admonebis(fut.)/admonueris(fut. perf.), non meminerint(fut. perf.).


Subjunctive Ideal/Imaginary Conditions

There is somewhat of a difference between what your book calls future ideal conditions and present or past ideal conditions.

Many other books would call a future ideal condition either a future less vivid (because it is not as vivid as the future more vivid which has future indicative) or a "should-would" condition (because it can be translated with should and would). Such conditions refer to a possible, but not strongly stated, future condition.

Typically the if-clause has "should" or "were to" and the then-clause has "would" in English.

Examples:
If he should come (or "were to come"), we would greet him warmly.
If you should leave (or "were to leave"), I would go too.
*Note the difference between the above future less vivid and the future more vivid: If he DOES come, we WILL greet him warmly. If you LEAVE, I WILL go too.

The present and past ideal conditions are often called unreal or contrafactual or contrary-to-fact conditions. A present contrary-to-fact condition states a present condition that is impossible or unreal. A past contrary-to-fact condition states a past condition that is impossible or unreal.

Typically a present contrary-to-fact condition has "were verbing"/"verbed" for the if-clause and "would verb" or "would be verbing" for the then-clause.

Typically a past contrary-to-fact condition has "had been verbing"/"had verbed" for the if-clause and "would have verbed" or "would have been verbing" for the then-clause.

Examples:
If he were leaving, we would go too. (but neither is true)
Were he coming, I would wait. (but neither is true)
We would not have left if he had gone. (but neither is true)
If you had come, I would not have joined in. (but neither is true)

English and Latin Examples of Subjunctive Conditions

Future Ideal/Future Less Vivid/"Should-Would": present subjunctive in Latin
If you should leave, I would follow.
Si discedas, sequar.
If he were to go, they would too.
Si eat, quoque eant.

Present Ideal/Present Unreal/Present Contrary-to-Fact: imperfect subjunctive in Latin
Unless you were leaving, you would not be sad.
Nisi discederes, non esses maestus.
If she were running (ran), she would win.
Si ea curreret, vinceret.

Past Ideal/Past Unreal/Past Contrary-to-Fact: pluperfect subjunctive in Latin
If you had run, you would have won.
Si cucurrisses, vicisses.
Unless he had left, we would have left soon.
Nisi discessisset, mox discessissemus.

One may mix present and past unreal:

If he had come, we would see him now.
Si venisset, eum nunc videremus.