If a book has a forward, introduction, or preface written by someone other than the author, I read it after finishing the book. I don’t want to tarnish my reading experience by learning anything about the contents beforehand. I like to experience the work unadorned so that I can form my own opinions. Also, I hate spoilers.
The preface to my copy of A Room of One’s Own by Virginia Woolf—which I duly read upon finishing the work itself—contains a delightful quotation from one of her other pieces. According to the preface, in her essay “How Should One Read a Book?” Woolf writes, “The only advice, indeed, that one person can give another about reading is to take no advice, to follow your own instincts, to use your own reason, to come to your own conclusions.”
You may think differently, but I think this is fabulous advice.
I also think that commentaries should be labeled afterword, conclusion, or, um, postface?—and be located accordingly. Readers would, in that case, be encouraged to read, reason, and conclude first and only later discover the opinions of another.
But what do you think?