1. Even if the sun were to rise in the west, I would never change my mind.

2. Even though the sun were to rise in the west, I would never change my mind.

3. Even if the sun were to rise in the west, I will never change my mind.

4. Even if the sun were to rise in the west, I could never change my mind.

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Are they the same in meaning?
Can we use 'will' instead of 'would' as in #3? What about #4? Is Sentence 4 right?

1 answer

All are correct and all mean approximately the same thing. The only slight difference is in 3, in which 'will' means 'never, never, never'!!