If you could improve one skill, which one would make the biggest difference in your life?

Question

If you could improve your knowledge or ability in one skill, what subject would you choose that would make the biggest difference in your life? And, how would learning it make a difference for you?

Answer 1

I'd choose to have a photographic memory.  That would make learning new things so much easier.  That's not really in one subject area so it's kind of cheating.  

If I had to choose a subject, it'd be finance.  If I was really clever and knowledgeable  in that area, I could make the most of my income through investments and be pretty well off.

Answer 2

I would improve my memory. Because if i could remember things, life would be a lot easier for me. I would remember what to buy at the grocery store, lol