The Eyes Have It

I don't get the phrase...or idiom...or metaphor...whatever the damn thing is...of to have an eye for.

As in...Gretchen has an eye for fashion.

Why is it singular? Gretchen has eyes for fashion. I know it makes no sense that way...but that's because the singular version has been in existence for forever...so get rid of that initial trepidation and look again...Gretchen has eyes for fashion. What's wrong with that? And why does one only have an eye for something...or come to think of it...an ear for something! What's going on??

I can kind of make sense of it to a degree...if you have an eye for art or something...you look at the piece of art with an eye closed kind of ...or if you have an ear for music you might lean in to hear more...that makes sense...kind of...but other than that...I don't get it.

Also I can understand why it can't be plural...also to a degree...because the other phrase-y thing is: to have eyes for someone or something...that's a completely different connotation...but again...why should it be that way and not the other...why can't Gretchen have eyes for art...and then have an eye for Ricardo...eh? Why not? It's the chicken and the egg...the chicken and the egg.

Think about it and get back to me, would you?


Of course you won't.