In English class, whenever we had to write papers about symbolism and theme and such, I remember lots of grumbling about things like, "Did the author really intend the character's red dress to be the foreshadowing of her suicide, or are we making this harder than it needs to be?"
I think the answer is yes and yes. Sometimes a red dress is just a red dress. Other times authors leave clues for their readers.
A while back, I watched a "Behind the Making of" thingy on the movie The Sixth Sense, the one about the little boy, Cole, who sees dead people. The director, M. Night Shyamalan drew our attention to the color red, which they used very intentionally in the movie:
The color red is intentionally absent from most of the film, but is used prominently in a few isolated shots for "anything in the real world that has been tainted by the other world" and "to connote really explosively emotional moments and situations".
Examples include the door of the church where Cole seeks sanctuary; the color of the balloon, carpet, and Cole's sweater at the birthday party; the tent in which he first encounters Kyra; the volume numbers on Crowe's tape recorder; the doorknob on the locked basement door where Malcolm's office is located; The shirt that Anna wears at the restaurant; Kyra's mother's dress at the wake; and the shawl wrapped around the sleeping Anna when Malcolm realizes he is a ghost.
You may recall, there's never a moment in the movie where Cole is like, "Hey - whenever I see something red, something bad happens!" It would cheapen the effect. Symbolism works best when it's subtle, when it's there for the taking, but not pointed out with neon arrows.
There's nothing wrong with planning a symbol or two, like the intentional red in The Sixth Sense, but generally I think it works best when symbolism emerges organically. I don't mess much with it until after I've written my first draft, put it away for a few weeks, and have started my first read-through. If I notice that, say, twice in my manuscript my character tries to manipulate a social situation, and that both times she's wearing a dress she made, I'll consider drawing that out more. If it serves the story, of course.
Same with theme. I usually have one in mind when I'm writing the first draft, but almost always a different one pops out at me during the second draft. In one of my works-in-progress, the theme I had in mind during the first draft had to do with accepting help from others versus making it on your own. But in the second draft, I came across this:
“Whether or not Jasper's after her, I think we should stay out of it,” I rush to say. I know as soon as Mr. Parks finishes chewing class will begin, and I don’t want to bring this back up later. This whole conversation feels like a betrayal, somehow. “Meddling in people’s relationships has a way of messing things up for everybody.”
As Mr. Parks reaches for his water bottle, the clue that we’re about to begin, Jack says in a voice that sounds almost ominous, “So can minding your own business when you should speak up.”
When I wrote this, it was just the way the conversation came out. Madeline and Jack are on opposite sides of the debate, and that was simply his counterpoint to what she said. But when I did my read through, Madeline and Jack's opposite feelings leaped off the page. I started asking questions like: As the story unfolds, how would Madeline come to agree more with Jack, and how might Jack come to agree more with Madeline? As I work on edits, that's something I can draw out more in later scenes.
What about you? Do you intentionally put themes and symbols in your manuscripts, or do they happen on their own?