Open vs remote conditional (2025)

I have a question concerning an issue from 'The Cambridge Grammar of the English Language' by Rodney Huddleston and Goeffrey Pullum, 2002. The authors give the two sentences:

[1] If he had stayed in the army he would have become a colonel. [remote]
[2] If he stayed in the army he will have become a colonel. [open]

They state that whereas in [2] both the apodosis and the protasis (the matrix and the subordinate clause) are in past time, in [1] only the staying in the army is clearly in the past - the becoming a colonel may refer to the future, which may be made clear by adding the time adjunct before the end of the decade to both sentences, with the result that [1] may refer to the end of the current decade, and hence to the future, whilst [2] cannot.

And the question is why? We can say: He will have become a colonel by the end of the decade, can't we? So why is this possibility excluded from [2] when the time adjunct is added?

I am sure.

I understand [2] as: I quite know that he stayed in the army, and I am sure that, as he stayed, he became a colonel.
The if-clause is therefore factual and the will have become expresses an inference, a highly possible situation.

Sentence [2] works if you say: "If it is true that he stayed in the army, he will have become a colonel by now."

Or, as you suggest:

"If it is true that he stayed in the army, he will have become a colonel by the end of the decade."
But this period of time (the end of the decade) must be a decade in the past. It cannot be a decade in the future.

If it were a decade in the future, you would say:

"If it is true that he stayed in the army, he will become a colonel by the end of the decade." (replace the future perfect with a simple future)

Scorpion56 said:

But why is the replacement necessary? Could you possibly look this sentence:
He will have become a colonel by the end of the decade?
Is it correct or should I replace the perfect with asimple future here as well?

Click to expand...

It is the addition of previous clause, If he stayed in the army that positions the utterance in the past.
As a stand alone statement, the tense you use is fine.

From what follows and from my linguistic knowledge from other sources this issue is related to the scope of the perfect - in [1] the perfect has scope over the modal, as opposed to [2], wherein the perfect is semantically related to the become.

And now that I'm ruminating over this issue in the light of the above, it seems rather logical why the perfect in [2] excludes a future interpretation. Of course, any other comments and interpretations would be much welcome. The intuition of native speakers is always of paramount importance for me

Yes, I can follow their examples [61] and [62] and what internal and external perfect are, but I can't work out what sentence [ii] - your (2) - means. What in fact does 'If he stayed in the army' mean? It can refer to the past:

If he stayed in the army - I don't know whether he did or not . . .

or to the future:

If he stayed in the army - he's doing well there now, so he might stay . . .

and neither of those fits with any meaning I can work out for 'will have become'.

If he stayed in the army = If it is true that he stayed in the army; hence I assume in this sentence that he did stay.

The preterite stayed locates the time of orientation and does not express modal remoteness (thus I have marked it as open conditional).