Lectitans' Question of the Week: How much can we know about the author herself based on the content of the book? If you answer, please go over to her site and leave a link.
I think this question applies to any artist: writer, artist, actor, etc. How much of themselves is in their work? If we see an actor portray the perfect guy over and over and over again, we begin to believe that of the actor, even if in Real Life it's not true.
How much can we know? Everything and nothing. I often assume things about authors when I read certain books; and every now and then that assumption has proved true when I've read an interview or other essay about the author and the book. And other times, I find out I'm wrong; very very wrong.
Of course it's best -- and easily said -- that the book stand alone, independent of anything we "know" about the author. But that's easier said than done; what I try to do is be aware that I am making those types of assumptions and try not to hold them too close. Because the problem with the assumptions isn't that they are made; the problem is when actions are taken based on those assumptions -- or actions are taken based on those assumptions being proven false. Because when proven false, the reader may feel "betrayed."
But I don't think there is anything wrong with assumptions, in part because it's human nature and we do it with everything. The important thing is knowing you're doing it.
It's also true that you can tell a lot about a reader based on their review; in the recent discussions in the blogosphere about reviews, a few thru out the comments that this is more true of blog reviews than print reviews. I have to disagree with that; as I've read non blogger reviews that tell a lot about the reviewer.