The thought is that you see an episode of observation, experiment, or reasoning as confirming or infirming a hypothesis depending on whether your probability for it increases or decreases during the episode.
He was infirm of body but still keen of mind, and though it looked like he couldn't walk across the room, he crushed me in debate.
... a car firm was going two of the three thousand euros of a new car ...
... firm or that firm fades from the scene? ...