Evidentiality marks the source of information the speaker has for his or her statement


See:


Notes from European languages with an evidentiality system? (Reddit)

I know Estonian, Turkish and Abkhaz have an evidentiality system that is part of their grammars.

European languages have the subjunctive of course!

German has a less-used subjunctive used primarily to express allegation or reported speech. For example:

Er hat das Essen gegessen

He ate the food

The verb phrase here is in the perfect tense in the indicative mood, just as you describe above.

Then we have: Er hÀtte das Essen gegessen

He would have eaten the food

Here we have the same verb phrase in the subjunctive 2 (Konjunktiv II), which here expresses counterfactuality.

But then German has: Er habe das Essen gegessen

He (allegedly) ate the food

Here, the helping verb haben, which forms part of the perfect verbal phrase, looks at first glance to learners of German as if it is an incorrect 1st person singular conjugation, but that form here indicates the subjunctive 1 (Konjunktiv I), which usually expresses that the evidence for the statement is hearsay. Newspapers, for example, employ this version of the subjunctive extensively when reporting. In everyday speech, it’s usually limited to a kind of replacement for quoted speech, and even then, it’s fairly rare/formal.

I realised that we have some kind of analogue of this in English, just like the French example below, as in “he would have eaten the food [wouldn’t he?]”, which you can imagine someone saying/asking as a supposition or “inference” of what you imagine would have occurred.

Something similar exists in Romance languages, where modal/temporal suffixes also have the additional function of marking evidentiality. In French, the conditional marks indirect evidentiality (il aurait mangé la nourriture - I heard/I deduce that he ate the food), while in Italian the conditional is restricted to hearsay (avrebbe mangiato il cibo - I heard that he ate the food) while the future is used for inferences (avrà mangiato il cibo - I deduce that he ate the food).