Fifteen authors who've influenced you and whose writing will always be with you.
List the first fifteen authors who come to mind in no more than fifteen minutes.
Ursula K LeGuin
I chose writers that have a worldview that jibes with mine and when I read them, they colonize my mind and I start thinking the way they write (that's why it's so dangerous to read late-period Henry James, every thought starts taking forever). I didn't include any comic book artists because it's a different medium, viewing them as authors doesn't give the art enough props. Like, do I include Neil Gaiman even though I may never read Sandman again because the art was boring? But if you feel differently, or want to limit your list to fiction or 18th-century epistolary novels or Urdu poetry that's cool, just post your list in the comments.
Just don't be like this guy and include song lyricists such as the immortal Gary Numan. I mean, I love music, it makes your soul sing and all that, it can change your mood and cause you to jump around the house like a crazy person. However . . . call me a crotchety old librarian, but I think words without music or pictures just stretch the brain in a way other media don't. If you can't read or listen to or Kindle or iPad or download from Cory Doctorow's web site enough books to have 15 favorite authors, I have one thing to say to you:
(Sooo not safe for work, if you are at work don't look at it, I'm serious!)