How would you say "for all I know" using 限り/限る in Japanese?


The best I can think of is 僕が知る限り + fact + とは限らない. Does this work, are there
better alternatives?




If I understand you correctly, the phrase you're looking for is more about
entertaining extreme/absurd possibilities, or humorously saying how little you
know about the matter, rather than a sincere “to the extent of my knowledge”.

Variations on “知る限り” will work when you are being sincere, but it doesn't
really work in a sarcastic way. I'd say it's closer to a “to my knowledge” or
an “as far as I know”:

> 僕の知る限りではいい人だよ  
>  _As far as I know, he's a good person._

When you're just putting out some extreme possibilities, you might consider
variations on “可能性もある”. Literally, it means “there is even the possibility
that…”, but I think the sentiment can be close:

  * 35年という期間は長すぎて、働けなくなる可能性や、 **それこそ** 死んでしまう **可能性もあります**  
_35 years is such a long time, you could become unable to work, or for all you
know you could be dead._

  * あの人はあまりにもよくテレビに出ていて、毎回 別人の **可能性すらある**  
_He's on TV so frequently, for all I know it could be a different person each
time._

  * プロフィールは全くのデタラメの可能性もあるのです。相手が故意にウソをいってだまし、犯罪に巻き込もうとしている **可能性さえ考えられます**  
_Profiles can be completely fake. For all you know, the person may be lying to
deceive you, trying to involve you in a crime._

(Examples taken and edited from the internet.)




I think what you have is fine, but I would say it as 私の知っている限り.

