past simple vs past perfect in conditionals

Question

I was brushing up on usage of if-clauses and came across one misunderstanding. M. Swan provide some sentences as an example in the lesson about unrealised present and future possibilities:

1. If my mother had been alive, she would have been 80 next year.
2. If my mother were alive, she would be 80 next year.

These two sentences have exactly the same meaning and it's more-or-less clear to me.

He also provides the following example:

3. If I became President, I'd be a good one. -- (said by schoolboy)

Can it be said as:

4. If I had become President, I'd have been a good one.

with the same meaning?

I think, no it can't. This is because the situation is pure-imaginary at the moment and it doesn't relate to some unrealised past, present or future possibilities. Is my understanding correct?

Answer 1

There are three kinds of if-clauses. In each kind of if-clause, the tense of the verb communicates two important ideas about the condition that affects the main clause of the sentence. The tense of the verb in the if-clause communicates:

1. The time perspective of the condition

AND

2. The nature of the condition

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Let's consider the pair of Presidential conditions first:

If I became President, I'd be a good one. -- (said by schoolboy)

• Became is the past tense of become.
• The past tense creates a present time perspective, as in "If I knew, I would tell you," or, "If I had some money, I would buy that," (but the word became directs our attention to the future within that present time perspective).
• The past tense implies that the condition is improbable or impossible.
• The meaning of the sentence is:

"Probably, I am not becoming President, but I would be a good one, if I did."

It makes sense for a school boy's imagination to present that idea in a sentence. A school boy would not be in a position to say the second sentence about becoming President (of the United States) with any credibility:

If I had become President, I'd have been a good one.

• Had become is the past perfect tense of become.
• The past perfect tense creates a past time perspective.
• The past perfect tense implies that the condition is impossible.
• The meaning of the sentence is:

"I did not become President, but I would have been a good one, if I had."

Since a school boy is not old enough to run for President of the United Staes, it would have been nonsense, if he had said that. The sentence is something a loosing candidate might say.

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The second pair of conditions communicates some impossible alternatives to a death condition:

If my mother were alive, she would be 80 next year.

• Were is the past tense of is.
• The past tense creates a present time perspective
• The past tense implies that the condition is improbable or impossible.
• The meaning of the sentence is:

"My mother is not alive, but she would be 80 next year, if she were."*

The words next year could create the same kind of time confusion as the word become did in the Presidential pair, but next year is in reference to the present time perspective. The other if clause communicates a similar meaning from a different perspective:

If my mother had been alive, she would have been 80 next year.

• Had had been is the past perfect tense of is.
• The past perfect tense creates a past time perspective.
• The past perfect tense implies that the condition is impossible.
• The meaning of the sentence is:

"My mother was not alive, but she would have been 80 next year, if she had been."

This construction is awkward, because the words next year seem to conflict with the past time perspective, but because death is a permanent condition, the meaning of the sentence survives well enough in the readers mind.

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Conditional clauses can be confusing because:

1. The time perspective of if-clauses does not always match the tense of the verb.

AND

2. The verb also does the unique work of implying the nature of the condition.

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This question only compared the second and third conditional clauses, but to put them in perspective.

First conditional:

• uses the present tense of the verb
• creates a present or future time perspective
• implies an open condition, that is something considered real or possible

Second conditional:

• uses the past tense of the verb
• creates a present time perspective
• implies an unreal, improbable or impossible condition

Third conditional:

• uses the past perfect tense of the verb
• creates a past time perspective
• implies an unreal impossible condition

Some instructors refer to a zero conditional as a special case of the first conditional.

Answer 2

The use of the article 'a' is incorrect in your example. It should 'the president' because you are talking about a definite position or designation.

First let's convert your example into a question -

Suppose we ask this question to a schoolboy

1. What changes would you bring about in the current system if you became the President of USA?

This is safe to ask to a schoolboy. Because you know that he's not going to become the president. So it's kind of a fantasy question.

But if you are a journalist then you can't ask this question to a potential presidential candidate (like a senator - because for him becoming the president is not a fantasy but a political aspiration)

So then question would be

2. What changes would you bring about in the current system if you become the President of USA?

(Here in this question the verb 'become' is used in the present (and not 'became') depicting that he has a chance to become the president. So it's no more a fantasy question.)

Regarding your doubt (Can it be said as ---- with the same meaning? I think, no it can't. This's because the situation is pure-imaginary at the moment and it doesn't relate to some unrealised past, present or future possibilities.)

So the situation which you refer to as pure-imaginary only applies to a schoolboy and not to a potential candidate.

So it's perfectly fine for a potential candidate who has lost the election to say the following sentence

If I had become the president, i would have taken measures to control the rising inflation.

(The above sentence is said by someone who has actually gone through the process of presidential election and lost it or by someone who had a chance to become the president but couldn't become)

So a school-boy for whom becoming the president is not more than a fantasy can not say the above sentence. He can only say

1. If i became the president, i would do this thing. OR
2. If i were the president, i would do this thing / i would have done this thing.