It is the consistency of the information that matters for a good story, not its completeness. Indeed, you will often find that knowing little makes it easier to fit everything you know into a coherent pattern.
The confidence that individuals have in their beliefs depends mostly on the quality of the story they can tell about what they see, even if they see little.
An individual who expresses high confidence probably has a good story, which may or may not be true.
We can't live in a state of perpetual doubt, so we make up the best story possible and we live as if the story were true.
Our memory tells us stories, that is, what we get to keep from our experiences is a story.