Yesterday, I was discussing the German imperative with my wife. Due to habits formed in high school and college language courses, we tend to use the formal version of imperatives even with our toddler unless we think about it (for instance, “Kommen Sie hier!” vs “Komm hier!”). This got me thinking about how German has four imperatives: formal, informal, plural (“Kommt hier!” == “Y’all come here!”), and speaker-inclusive (e.g., “Gehen wir jetzt!” == “Let’s go now!”).
Standard English doesn’t distinguish between singular and plural in the second person, nor does it distinguish between formal and informal, so it makes sense that we wouldn’t have those distinctions. That leaves the speaker-inclusive form.
I was taught that the speaker-inclusive form of the English imperative is “Let’s” plus the infinitive, but it seems to me that “Let’s” is (at least historically) a contraction of “let us”; that is, “Let’s go” is not technically a speaker-inclusive imperative in the same sense as “Gehen wir,” but is rather a standard second-person imperative.
I say “at least historically” because “let’s” feels at least partially fossilized as a grammatical token rather than a semantically meaningful element. In general, “us” is ambiguous between an audience-inclusive and an audience-exclusive interpretation; “us” merely means “me and at least one other person,” and context is needed to determine whether “you” is included.
However, “let’s” is not ambiguous in this manner; it includes the speaker and the audience (and possibly others). In contrast, “let us” is ambiguous, and weakly implies an audience-exclusive interpretation:
1. Let's go! 2. Let us go!
Of these, only (2) can be used in a hostage situation where captives are pleading for their release to a captor. Likewise, (2) is at least somewhat stilted in a situation where the speaker is trying to urge someone to leave with him.
In German, this distinction is made by using either the first-person imperative or the second-person passive imperative:
1'. Gehen wir! 2'. Lassen Sie (lass/lasst) uns gehen!
(although in the sense of being released from captivity, “Befreien Sie mich!” would be more appropriate).
One reason why this is interesting to me is that I feel strongly that the words and structures that we choose to use in a language has an effect on how we perceive. In English, when we were developing our imperative, we apparently felt that it was implicit in a communal imperative that the speaker would be involved, and therefore the first person imperative is a form of a request: “Will you allow us to do X?” German, meanwhile, makes no such implication; the imperative is a command to both the audience and the speaker.
An afterthought: I’m also intrigued that German imperative requires the use of the pronouns “Sie” (formal) and “wir” (first person plural) but not “du” (informal) or “ihr” (plural). I don’t know what the historical reason for this is, but it does occur to me that the Sie and wir forms are always the same, and hence dropping the pronouns would create potential ambiguities, while the du and ihr forms are usually if not always different.