Is "could" more sure than "may" or "might"?

[sitifan]

The keys may/might/could be in one of those drawers.
According to A Basic English Grammar by John Eastwood and Ronald Mackin, could is rather less sure than may or might. There is little difference between may and might, but a speaker who uses might is a little less sure.
According to A New English Grammar by Zhang Zhenbang, could is more sure than may or might.

Which book is correct?

 

[5jj]

The keys may/might/could be in one of those drawers.

Which book does that come from?

Which book is correct?

There is no 'correct' answer as such. People have different feelings about such modals. My own feelings are closer to those of Eastwood and Mackin than those of Zhang Zhenbang.

 

[jutfrank]

According to A Basic English Grammar by John Eastwood and Ronald Mackin, could is rather less sure than may or might.

I think that's wrong. I mean, I understand what they're saying and why, but I don't think it's a good explanation.

There is little difference between may and might, but a speaker who uses might is a little less sure.

I think that's just plain wrong.

According to A New English Grammar by Zhang Zhenbang, could is more sure than may or might.

That's a novel idea! I've never heard of anyone who thinks that, and I don't know why anyone would.

The difference in modality between these words is not best explained with a spectrum of certainty, in my opinion. I prefer to explain this difference as qualitative—about different kinds of possibility—rather than as quantitative by degree. In some sense, the kind of possibility we get from could is more 'remote' from might, but not really less 'sure'.

 

[sitifan]

Which book does that come from?

The keys may/might/could be in one of those drawers.
The above sentence comes from A Basic English Grammar by John Eastwood and Ronald Mackin.

 

[sitifan]

It might be George.
It may be George.
It could be George.
? It can be George.
It should be George.
It ought to be George.
It would be George.
It will be George.
It must be George.
The above spectrum of certainty (from the least certain to the most certain) is quoted from A New English Grammar by Zhang Zhenbang, page 640.

 

[5jj]

A random selection would have been as good.

 

[emsr2d2]

In that list, only "will" and "must" have any degree of certainty (100%). All the others are simply not 100% certain.

 

[jutfrank]

It might be George.
It may be George.
It could be George.
? It can be George.
It should be George.
It ought to be George.
It would be George.
It will be George.
It must be George.
The above spectrum of certainty (from the least certain to the most certain) is quoted from A New English Grammar by Zhang Zhenbang, page 640.

This is either a shocking misunderstanding or a hopelessly optimistic simplification. I can't tell which one it is.

 

[emsr2d2]

This is either a shocking misunderstanding or a hopelessly optimistic simplification. I can't tell which one it is.

Given the rest of the content we've seen from that "teacher", I'll go for both.

 

[kadioguy]

The difference in modality between these words is not best explained with a spectrum of certainty, in my opinion. I prefer to explain this difference as qualitative—about different kinds of possibility—rather than as quantitative by degree. In some sense, the kind of possibility we get from could is more 'remote' from might, but not really less 'sure'.

Could you please explain that a little bit more? I mean, like, what the kind of possibility do we get from could? And what kind from might?

 

[dunchee]

Could you please explain that a little bit more? I mean, like, what the kind of possibility do we get from could? And what kind from might?

Cambridge Dictionary | English Dictionary, Translations & Thesaurus

The most popular dictionary and thesaurus for learners of English. Meanings and definitions of words with pronunciations and translations.

dictionary.cambridge.org

- could B1 ...
- might A2 ...

and

Could, may and might

Could, may and might - English Grammar Today - a reference to written and spoken English grammar and usage - Cambridge Dictionary

dictionary.cambridge.org

- Compare ...

 

[5jj]

I think these words in the second link sum it up: We use could, may and might to express degrees of possibility. Many native speakers disagree on which one expresses more or less certainty.

 

[jutfrank]

Could you please explain that a little bit more? I mean, like, what the kind of possibility do we get from could? And what kind from might?

In my terms, I say that 'might' commonly expresses real possibility whereas 'could' expresses theoretical possibility.

Here's a simple example to begin to show what I mean:

a) I might go out tonight.
b) I could go out tonight.

Utterance a) would be used only if I were seriously thinking about the option of going out. It's real in the sense that it has some bearing on the real world.
Utterance b) says only that there is nothing stopping me from going out. I might say this even if I had no intention of going out whatsoever. It's purely theoretical.

This difference has nothing to do with certainty, in my opinion.

 

[Tarheel]

You could flesh them out thusly:

I might go out tonight. Then again, I might not.

I could go out tonight if I wanted to, which I don't.