Past Hypothesis vs Past Condition

Question

I know the title might look confusing, so I would like to explain it in detail here.

As far as I know, we can use past perfect construction when referring to a situation that didn't happen in the past, which is a hypothetical situation.

For example,

1. If you had told me earlier, I could have fixed it.

And you can use simple past when referring to what would happen if something happened, as a condition that might have actually happened in the past.

2. If someone talked to me like this three years ago, I would punch him in the face.
   (You would actually do that because that's how you always did three years ago)

Here I would like to ask whether the distinction I made is correct.

For example,

3. If he had needed someone to help him three years ago, he would have just asked.
   (He didn't need anyone to help him three years ago)

4. If he needed someone to help him three years ago, he would just ask.
   (There might have been occasions when he needed someone to help, and he most of the time just asked, or at least that's what would possibly happen if he needed some help three years ago)

Answer 1

I think the assumption you are starting with is incorrect.

"Past Perfect tense" when referring to a situation that didn't happen in the past, which is a hypothetic situation. [ a hypothetical situation]

Past and past perfect apply to events in the past whether they occurred or not. What matters is when each happened. There is also present and present perfect but not part of your question. The hypothesis vs condition question is strange. A hypothesis is a description of a condition or situation; a hypothetical condition. Their truth condition has no bearing on the tense used.

The distinction you are looking for is this;

"he would have just asked." vs "he would just ask."

The past tense of ask shows you may already understand a bit. The conditions of when he would have asked is detailed in the sentence about the past. Example; With the resources he had long ago if he needed help he would have just asked. This indicates he could not ask since that time has passed. Placing the description in the past means his actions then were dependent of conditions then. Even as all the events are in the past they are still relative in time to one another.

I'm sure "he would just ask." would be understood without a problem but means something slightly different; particularly that he would/could still ask for help now despite the conditions of long ago.

Answer 2

You have correctly analysed the two sentences with the past perfect tense in the if-clause as 'hypothetic' or counterfactual/non-factual, i.e. you didn't tell me and he didn't need help.

However, the sentences with the past simple in the if clause are not hypothetical or non-factual. They say what did in fact happen. The would + infinitive in the main clause could be replaced by the simple past and retain the same meaning:

• If someone talked to me like this three years ago, I punched him in the face.
• If he needed someone to help him three years ago, he just asked.

The if in the two past simple sentences above could be replaced by when/whenever. This is not possible in the past perfect sentences.

Swan in Practical English Usage (p622) says that would (as exemplified in the past simple sentences here) is used for 'typical behaviour in the past'. His examples:

• Sometimes he would bring me little presents without saying why.

• On Sundays when I was a child we would all get up early and go fishing.

Note that would + infinitive can be used in sentences with the past simple in the if-clause, but these sentences are either 1. counterfactual about the present or 2. hypothetical about the future:

• 1. If I had time. I would help you (but I don't have time).
• 2. If I won the lottery, I would quit my job.
• 2. If someone talked to me like that, I would punch him in the face.