I'm sorry if this may seem TOO simple of a question and I may seem stupid to ask it, but I want some clarity on this matter.
How do you name the key of a piece? I have always thought that you name it depending on what key signature it is on, for instance, Bach's Minuet in G which has one sharp therefore G. What boggles me is that in Chopin's Fantasie Impromptu Op. 66 in C# has four sharps isn't that supposed to be in E?
I hope that you would consider and give the time to answer a beginner's question. Thank you.
Beginner Question on Music Theory