Hello Nolfese,
The thing is, English "we" can be specific, when you know exactly which people are included in the group... or it can be general, like
on. Furthermore, when we want to be general, we can often use "you" as well, without addressing our comments to any specific person. In fact, we (general) often use "we" or "you" rather than "one," in English, as "one" can sound quite stiff. Compare:
Must one tell all?
Must we tell all?
Is it our lot to go through life alone?
Is it one's lot to go through life alone?
(Do you have to tell all?)
(Do you have to go through life alone?)
You would understand the same general meaning for both the "we" and the "one" version of these sentences, I believe, but the 1st person wording probably feels more natural.
So how do you interpret the French
on, as "we" or as "one"? Well when it's clear that
on refers to a specific group whose members could be identified, then you have an informal replacement of
nous by
on. But when there is no specific group, you have a generic usage... and whether the most natural translation will use "we" or "one" in English is going to depend on the context.
Note, however, that there's a definite difference between "one" and "someone." "One" potentially includes you, whereas "someone" implies more of a 3rd party. Using
on to imply a 3rd party is less frequent (unless that unique person is identity unknown or deliberately kept anonymous); you'll see
quelqu'un instead. I don't see how any of the
on pronouns in these lyrics could mean "someone (else)."
Hope that helps.
Jann
P.S. If those lyrics are transcribed correctly, it cannot be
on raconte que quelque chose nous revienne (because that subjunctive would be unjustified). So it would have be an ellipsis, referring back to the previous line:
faut-il encore que quelque chose nous revienne.