🚀 go-pugleaf

I prefer to think of metamessage instead of theme.  For the story I am
currently writing the theme is keeping looking for Mr. Right, he will show
up.  With a theme like this it's obviously a romance.  
Even trivial books have themes.  I recently read Winter World: Brander's Book by
C.J. Mills. an example of space opera.  The theme is be
self-reliant and don't trust anyone.  (corollary-If you do trust anyone, they
will hurt you.)  The themes in Jane Austen's books are be yourself and someone
will love you.  (Perhaps even Mr. Darcy)  The books I reread are ones whose
themes I want to reinforce in my life.  So I read a lot of Jane Austen.  

A wonderful example of the power of a theme is Star Trek, both the original and
The Next Generation.  One aspect of its theme is that the future is wonderful 
And just think of all the people who are attracted to that theme.
 
I also believe that writing is like the other fine arts.  A composer writes a
song to evoke a particular mood, or to suggest a particular scene.  A writer
of fiction shows us a world of his/her own imagination.  This comes complete with
the person's biases and experiences.  The theme of the book results partly from
the author's character and partly from his/her conscious decisions in writing the
book.