Which languages conflate (imperfective) past and irrealis, and why?

Question

In English, the "simple past" form of a verb can sometimes be used to convey irrealis meanings, without any preterite sense:

1. If I was rich, I'd buy a Porsche.
2. If you only knew!
3. I wish I was there with you.
4. I'd like to be able to say that he wrote brilliant poetry, but he doesn't.
5. It's time you went to sleep.

I can think of several other languages that do this, including French ("si j'étais riche..."), Ancient Greek, and Modern Hebrew. In languages that have an aspect distinction, it seems to be specifically the imperfective past tense that does this.

Three questions:

1. What is the specific set of irrealis contexts (e.g. counterfactual conditionals, etc.) in which past-tense forms can be used in English, and how does it differ from that of other languages that have this conflation? For example, in Hebrew, the conditional examples 1-3 above would be translated with a past-tense verb, but example 4 would need a present form and 5 a future.
2. How widespread is this phenomenon? What other languages do this? Is it a European or Indo-European thing, or is it broader than that? (Hebrew is neither of these, of course, but Modern Hebrew got much of its syntax and idiom from European languages, so could have borrowed this.)
3. What is the basis for this syncretism? Past and irrealis seem to have nothing in common; if anything, it would make more sense to line up past with realis and future with irrealis. Imperfective and irrealis maybe have a little more in common in that neither expresses a specific, single, real event, but this still doesn't seem like much. Given that this is a recurrent pattern across several languages, is there a cognitive reason for it?

Answer 1

For most Romance languages at least, there's a totally separate set of conjugation forms called the "subjunctive mode", used to indicate things that could/should/might be, could/should/might become, or that somebody wishes they did as opposed to the "indicative mode" which usually indicates stuff the way it is. Usually, subjunctive present has nothing to do with indicative past, nor subjunctive past with indicative past perfect.

Even French does this, except its imperfect doubles work as a kind of subjunctive after conditional "Si" (If). So you do can say "Si j'étais riche" but you must say "Quand je sois riche" for "Quand j'étais riche" implies you have already been rich, but aren't anymore.

Problem with English is that over time its subjunctive present has mostly merged with indicative past, subj. past with ind. past perfect and so on. Only exception is verb "to be" in formal settings, which goes "if I were you" and "I wish he were a writer" (which both change to "was" in colloquial settings - apparently native speakers can't resist regularizing the conjugation pattern).

Latin future tense disappeared in the Vulgar form of the language, reappearing in Middle Ages by using verb "to have" as an auxiliary: "Yo iré" comes from "Yo ir he" (literally "I to go have"), same happened in French with "J'amerai", Italian "Io parleró", etc. Don't know much about proto-Germanic but at least English evolved in a similar way using "to have" or "to shall" for the future. So even if native speakers did feel an affinity between irrealis and the future, the lack of a grammatical future tense most probably stopped such merge to happen.

Answer 2

I suspect subjunctive merged with indicative in English simply due to phonetical reasons. Look at Old English:

"I ate" (indicative) - Ic æt

"I ate" (subjunctive) - Ic æte

or

"we beat" (indicative) - bēoton

"we beat" (subjunctive) - bēoten

(according to wiktionary)

Then vowel reduction happened, and unstressed vowels in affixes all turned into schwas or zero, it's not surprising that forms like bēoton and bēoten merged into one single "beat" both for simple past and subjunctive, as it is today.

I also looked at Proto-Germanic, and subjunctive forms differ from indicative forms there only slightly too:

"you did" (indicative) - *dedēz

"you did" (subjunctive) - *dēdīz

or

"he did" (indicative) - *dedē

"he did" (subjunctive) - *dēdī

It was just bound to collapse phonetically, all those endings eventually collapse into schwas in Germanic languages due to the fact that Germanic languages have strong expiratory stress closer to the beginning of a word.

If you look at "to be", then you can see a pattern that still survives today to an extent:

"I was" (indicative) - Ic wæs

"I were" (subjunctive) - Ic wǣre

Was/were still survives to this day, because there was no phonetical collapse like above (thanks to rhotacism wǣse > wǣre between vowels). And, obviously, modern "if I was" is just analogical, because 99% other verbs do not tell between subj. and indicative.

Answer 3

If I could address the Semitic part of your question: the Arabic past tense (al-māḍī; please note that this word actually does mean “past”) is used in principal clauses for actions in the past time, but is also used with the particle “law” in unreal conditions. So at least in your first two sentences you would say “law kuntu” and “law kunta”. So this is not a purely Indo-European thing.

Answer 4

At least in my dialect of Spanish (Rioplatense) sometimes the imperfect past tense is used instead of both the subjunctive and the potential in conditional sentences (as exemplified below). This is colloquial and I'm sure many people would view it as ungrammatical, but is used often enough.

Si sabía no te decía.

• Literally: "If I knew, I didn't tell you" (both imperfect, maybe rather like "If I was knowing, I wasn't telling you").
• Actual meaning: "If I had known, I wouldn't have told you."
• "Correct" form: "Si hubiese sabido no te habría dicho."

Si me iba hace cinco minutos no me enteraba.

• Literally: "If I went five minutes ago, I didn't learn of it."
• Actual meaning: "If I'd gone away five minutes ago, I wouldn't have learned of it."
• "Correct" form: "Si me hubiese ido hace cinco minutos no me habría enterado."

I've heard the same kind of construction in Brazilian Portuguese but I'm not confident enough about their usage.