Filter words

Filter words are verbs of perception — saw, heard, felt, noticed, realised, wondered — that place the character between the reader and the thing being perceived, adding a layer the sentence usually does not need.

She saw the door swing open. Compare: The door swung open. The second is shorter, and it is closer — we are watching the door instead of watching her watch the door. The narration is already inside her head, so the reader never doubted whose eyes these were.

The usual suspects: saw, heard, felt, smelled, tasted, noticed, watched, observed, realised, wondered, thought, decided, seemed, looked like. Searching for those words is a standard self-editing pass, and deleting most of them quietly moves the prose into free indirect discourse.

It is not a ban. Filters earn their place when the perceiving is itself the point — She heard it before she saw it depends entirely on that order — or when a perception needs to be marked as uncertain, partial or mistaken. He thought she was smiling does work that she was smiling cannot do.

The rule is that every filter should be a choice rather than a habit. A line edit will usually remove most of them and leave the few that are load-bearing.