I love Chuck Palahniuk’s advice to writers:
From this point forward – at least for the next half year – you may not use “thought” verbs. These include: Thinks, Knows, Understands, Realizes, Believes, Wants, Remembers, Imagines, Desires, and a hundred others you love to use.
Palahniuk argues that every time you use one of these verbs, you’re robbing yourself of the chance to describe something fully — to show rather than tell.
For example: Waiting for the bus, Mark started to worry about how long the trip would take..”
A better break-down might be: “The schedule said the bus would come by at noon, but Mark’s watch said it was already 11:57. You could see all the way down the road, as far as the Mall, and not see a bus. No doubt, the driver was parked at the turn-around, the far end of the line, taking a nap. The driver was kicked back, asleep, and Mark was going to be late. Or worse, the driver was drinking, and he’d pull up drunk and charge Mark seventy-five cents for death in a fiery traffic accident…”
In screenwriting, we’re already forced to do a lot of this self-restriction, since we can’t directly state characters’ inner lives. And Palahniuk’s absolutism isn’t always suited for screenplays; there will be times when a parenthetical (realizing) is exactly what you need.
Still: it’s great advice.