If every unspoken thought appeared as an object, some apparently empty rooms would become impassable.

Unspoken things take up space. If they were visible you would see rooms crowded to the ceiling with what nobody said, and the silence that currently looks like calm would be revealed as extremely full. Absence of speech is not absence of content.

So treat quiet rooms with a little suspicion, in a family, in a team, in a friendship that has gone smooth. Ask what is not being said, and be prepared to go first. Saying one of your own unspoken things is usually what makes room for anybody else’s.