If not

[Anna232]

This sentence and explanation is from my book English Grammar Practice by L.G. Alexander.

We often use unless (never if not...) to introduce an afterthought
I coudn't have got to the meeting-unless, of course, I had caught an earlier train.
What does the part in bold mean? Does the sentence mean that he managed to get to the meeting?

 

[5jj]

He did not.

 

[Anna232]

He did not.

I thought it means I coudn't have done that if I didn't catch the train. I am confused. Can it have this meaning too?

 

[jutfrank]

The bold part means we never use 'if not'.

The sentence means that he did not attend the meeting. In the first clause of the sentence, the speaker is saying that it was impossible to attend. In the second clause (with 'unless'), the speaker is adding an afterthought by mentioning that there could have been one condition upon which it was possible to attend, and that condition was his taking an earlier train. Compare this meaning with the same sentence using 'if not' instead of 'unless':

I couldn't have got to the meeting if I hadn't taken an early train.

In this sentence, the speaker did attend the meeting.

 

[5jj]

1. I couldn't have got to the meeting If I hadn't caught an earlier train.
I did catch an earlier train and I did get to the meeting.

2. I could have got to the meeting if I had caught an earlier train.
I didn't catch an earlier train and I didn't get to the meeting.

3. I couldn't have got to the meeting-unless, of course, I had caught an earlier train.
I didn't catch an earlier train and I didn't get to the meeting.

 

[Anna232]

1. I couldn't have got to the meeting If I hadn't caught an earlier train.
I did catch an earlier train and I did get to the meeting.

2. I could have got to the meeting if I had caught an earlier train.
I didn't catch an earlier train and I didn't get to the meeting.

3. I couldn't have got to the meeting-unless, of course, I had caught an earlier train.
I didn't catch an earlier train and I didn't get to the meeting.

The first two sentences are easy to understand. In #3 I understand "unless I had caught" to mean "if I did not do that" and that's why I thought it means he caught the train and attended the meeting.
But what kind of conditional sentence is #3? Usually "unless" means "if not." As in "You won't pass your exams unless you study for them."

 

[Anna232]

The bold part means we never use 'if not'.

The sentence means that he did not attend the meeting. In the first clause of the sentence, the speaker is saying that it was impossible to attend. In the second clause (with 'unless'), the speaker is adding an afterthought by mentioning that there could have been one condition upon which it was possible to attend, and that condition was his taking an earlier train. Compare this meaning with the same sentence using 'if not' instead of 'unless':

I couldn't have got to the meeting if I hadn't taken an early train.

In this sentence, the speaker did attend the meeting.

But depending on context in some situations "unless he had done" can have the same meaning as "if he did not." When something did happen. Right? Because in the second example the idea is that he did trip.

I wouldn't suggest such a plan unless I thought it was feasible.

Regarding the use of 'unless in a remote conditional, The Cambridge Grammar (p755) says: Unless occurs in open conditionals and, less freely, remote ones: [52] ... iv I wouldn't suggest such a plan unless I thought it was feasible. ... The implicature of the remote version, as in [iv], is that...

forum.wordreference.com

Post #13
1.If he had not tripped, he would not have lost. :tick:
2.Unless he had tripped, he would not have lost.

 

[5jj]

Usually "unless" means "if not." As in "You won't pass your exams unless you study for them."

Unless is frequently presented as an alternative to IF...NOT, and some English course books give exercises in which learners must change one form into the other, with the [sometimes explicit] idea that there is no difference in meaning between such utterances as:

I'm going swimming tomorrow if it doesn't rain. I'm going swimming tomorrow unless it rains.

In fact, as always, if a different word is used, there is a degree of difference in meaning, even if the practical difference is small. IF suggests uncertainty about the possibility of rain, and consequent uncertainty about the possibility of going swimming. UNLESS has a meaning similar to except in the following situation or if and only if ... not; the certainty of going swimming is greater in the speaker's mind in the first than in the second. How great or small the certainty is within the speaker's mind in is of course known only to the speaker at the time of utterance.

This is why in counterfactual hypotheses about the past, UNLESS is far less commonly used. In the first sentence, below the speaker mentions one situation that would have made his parents unhappy; the possibility exists of there being other situations that would equally have made them unhappy. The second sentence would imply that the parents would have been unhappy in every contingency except the speaker's going to university - theoretically possible but unlikely.

My parents would have been unhappy if I hadn't gone to university.

? My parents would have been unhappy unless I had gone to university.

In addition, as we have seen, the use of UNLESS implies that the certainty of the occurrence of the situation in the consequent clause is greater than with IF...NOT. The speaker is not likely to imply greater certainty of occurrence of something that he or she knows did not occur.

 

[Anna232]

Unless is frequently presented as an alternative to IF...NOT, and some English course books give exercises in which learners must change one form into the other, with the [sometimes explicit] idea that there is no difference in meaning between such utterances as:

I'm going swimming tomorrow if it doesn't rain. I'm going swimming tomorrow unless it rains.

In fact, as always, if a different word is used, there is a degree of difference in meaning, even if the practical difference is small. IF suggests uncertainty about the possibility of rain, and consequent uncertainty about the possibility of going swimming. UNLESS has a meaning similar to except in the following situation or if and only if ... not; the certainty of going swimming is greater in the speaker's mind in the first than in the second. How great or small the certainty is within the speaker's mind in is of course known only to the speaker at the time of utterance.

This is why in counterfactual hypotheses about the past, UNLESS is far less commonly used. In the first sentence, below the speaker mentions one situation that would have made his parents unhappy; the possibility exists of there being other situations that would equally have made them unhappy. The second sentence would imply that the parents would have been unhappy in every contingency except the speaker's going to university - theoretically possible but unlikely.

My parents would have been unhappy if I hadn't gone to university.

? My parents would have been unhappy unless I had gone to university.

In addition, as we have seen, the use of UNLESS implies that the certainty of the occurrence of the situation in the consequent clause is greater than with IF...NOT. The speaker is not likely to imply greater certainty of occurrence of something that he or she knows did not occur.

Thank you so much for such a detailed explanation. Could you please explain this part?

"The second sentence would imply that the parents would have been unhappy in every contingency except the speaker's going to university - theoretically possible but unlikely.
? My parents would have been unhappy unless I had gone to university"

Did he go to university or not?

 

[jutfrank]

What's confusing you is that the use of 'unless' in the original sentence of post #1 is a special case where the phrase 'unless, of course' is used as an afterthought. Because it's an afterthought, you should treat it as a new and logically distinct utterance because it does not affect whether the previous part was true. In fact, importantly, it contradicts what was said before. This contradiction is what you're struggling to understand.

Let me write the passage in a different way, to show you what I mean:

I couldn't have got to the meeting. Unless, of course, I had taken an earlier train.

I've written it in two separate sentences to show the meaning of the first utterance more clearly. The meaning of the first utterance is not logically connected to the second. By reading the first sentence, you know that it was not possible for the speaker to go to the meeting, and so you know he didn't go. The second sentence is only an afterthought, where the speaker qualifies what he has just said. If this afterthought were to be written in its logical entirety, it would look like this:

I could have got to the meeting if I had taken an earlier train.

As per the usual logic of counterfactual sentences, you can hopefully understand from this that the speaker did not attend the meeting.

The original example sentence uses a dash rather than two separate sentences, which is fine. You could also use an ellipsis to do the same job:

I couldn't have got to the meeting ... unless, of course, I had taken an earlier train.

 

[Anna232]

What's confusing you is that the use of 'unless' in the original sentence of post #1 is a special case where the phrase 'unless, of course' is used as an afterthought. Because it's an afterthought, you should treat it as a new and logically distinct utterance because it does not affect whether the previous part was true. In fact, importantly, it contradicts what was said before. This contradiction is what you're struggling to understand.

Let me write the passage in a different way, to show you what I mean:

I couldn't have got to the meeting. Unless, of course, I had caught an earlier train.

I've written it in two separate sentences to show the meaning of the first utterance more clearly. The meaning of the first utterance is not logically connected to the second. By reading the first sentence, you know that it was not possible for the speaker to go to the meeting, and so you know he didn't go. The second sentence is only an afterthought, where the speaker qualifies what he has just said. If this afterthought were to be written in its logical entirety, it would look like this:

I could have got to the meeting if I had taken the earlier train.

As per the usual logic of counterfactual sentences, you can hopefully understand from this that the speaker did not attend the meeting.

The original example sentence uses a dash rather than two separate sentences, which is fine. You could also use an ellipsis to do the same job:

I couldn't have got to the meeting ... unless, of course, I had caught an earlier train.

Instead of using "If I had taken" when the action didn't happen I can use "unless I had taken". As In "I coudn't have passed the exam, unless I had hired a private tutor." I understand the second part to mean "on condition if I did that" but I didn't. Am I right? As in I coudn't have passed the exam but if I had hired a tutor which I didn't, I would have passed it.

 

[Tarheel]

"Instead of" and "also" don't go together.

 

[Anna232]

"Instead of" and "also" don't go together.

I have just edited it.

 

[Tarheel]

I have just edited it.

OK, but that post still hurts my head. (I have some acetaminophen tablets in a small bottle. I'm thinking about using them. )

 

[Tarheel]

This sentence and explanation is from my book English Grammar Practice by L.G. Alexander.

We often use unless (never if not...) to introduce an afterthought
I couLdn't have got to the meeting-unless, of course, I had caught an earlier train.

No. The first thing I would want to know would be the context. (There probably isn't any.) In other words, why did the speaker say that?

There has to be a reason to say something or you don't say it.

Perhaps:

Abe: Why weren't you at the meeting?
Bob: I wasn't able to make it.

I wouldn't bother saying what's not used.

Don't try to put everything in one sentence. You'll just confuse yourself. Don't complicate things unnecessarily.