People
A man receives only what he is ready to receive... The phenomenon or fact that cannot in any wise be linked with the rest of what he has observed, he does not observe.
— Henry David Thoreau

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker argues that noticing depends on being ready to connect something new with something already understood. An unfamiliar fact may pass unobserved if it has no place in that framework. The passage presents attention as shaped by the knowledge brought to an encounter.
Context reviewed