I was driving the car the other day when a bright idea popped into my head. An element for the work in progress that would give the protagonist an added reason be involved. Not a big deal to write. Would involve a few extra paragraphs scattered here and there. Perhaps a morning's work at the most.

So here's the dilemma for the day.
<blockquote>a) Do I just step in straight away and commit that change to paper? Or...

b) Sit on it, think about the change for a while, then put it into action another day?</blockquote>
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Those of you who answered b) go buy yourself a lollipop. The a) people can stand in the corner and ask yourself: what <em>have</em> I done?

Trust me. I'm an airhead whose mind is constantly spinning with ideas, possibilities, changes, alternative versions. I have been through this quandary a million times. If I've learned one thing about writing it's this... <em>never, ever act on impulse.</em>

First reason: you may just be plain wrong. Today's bright idea is tomorrow's 'How could I possibly be so stupid?' revelation. Impulsive notions always seem attractive when you have them. We're built that way. It's our brains rewarding themselves for being so clever in coming up with the thing in the first place. It doesn't mean they're right. And the worst thing of all is this: bright ideas invariably mean something substantial. A new facet to a character. A different possible direction for a story thread or even the whole book. You can rarely undo them just by taking out the bits you put in the manuscript when the idea hit. You'll usually have to unpick all the difficult threading from the point after up to the moment you realise it wasn't a great idea after all. Not good.

Second reason: bright ideas mid-book always, always involve adding things in. Making something longer and, yes, more complicated. As a general rule books are improved by taking stuff out. Better to finish your first draft with something that's underwritten than overwritten. It's more efficient and more effective to look at that book in waiting and think... a touch here and a touch there... than to spend your time trying to understand what to excise. Better use of your editor's time too if you have one.

When I have bright ideas I treat them like this. They go in my book diary immediately as a possibility. I sit on them for a day or two. Then I look at them in the cold hard light of day with the perspective a little time brings to that bright spark moment. If I'm really convinced they're a good idea they go in. If I'm not sure they either stay out or I save a copy of the draft as a backup and try a fresh version with the spark in to see if it works.

Bright ideas are great before writing and after you've finished. But when they crop up mid-book they need to be treated with caution because sooner or later you will hit that 'I know -- the guy could be a vampire!' moment.

Best avoided, honestly.

Footnote: after sleeping on this one for a couple of nights I decided it was a very good idea indeed and inserted it into the manuscript. But not before saving a backup copy I can return to without it if need be.