Another interpretation of this second conditional sentence

Consider:

If I met John, I would call my mom.

I know this sentence is a second conditional example, which relates to a hypothetical situation.

But I don't know whether I can also understand it in such a way if the covert context is:

I may have met him, but I am not quite sure about that. My memory can't last that long. The only thing I am sure about is that whenever I meet him, I will call my mom immediately. Thus, if one day I find out I indeed met John before, I will be sure that I called my mom immediately on that occasion.

Answer

This is exactly why the notion of '1st, 2nd, 3rd conditional' is so useless for anything except getting an initial familiarity with the forms. This sentence, as you conjecture, bears two entirely different meanings in different contexts:

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  It may be a non-past, unreal conditional:

  
  

  
  

  I don't follow football, but in the unlikely event that I ever met John Elway I would call my mother immediately: she's a huge fan of his.

  
  

  
  



• 
  

  It may be a past, real conditional:

  
  

  
  

  That summer, Mom didn't mind who I played with as long as she knew where I was; so whenever I met John I would always call my mother.

  
  

  
  

Your scenario—“I am not sure whether I met him sometime last summer. But if I did meet him at that time, I would call my mom and tell her about him.” requires a different construction in the consequence clause, and would probably employ a construction with do in the condition clause:

I don’t remember if I met John last summer; but if I did meet him, I would have called my mother.

The n-conditional model won’t help you with that: it waves the situation off as a ’mixed conditional’.