For example, suppose that whenever Alice talks about plums, Bob makes a subtle disapproving gesture, like a slight look of annoyance, or briefly turning away, or hardening the tone of his voice a bit.
Perhaps Alice might notice that she mysteriously dislikes mentioning plums in Bob’s presence, but not when she is with other people. In that case, she might consider the hypothesis that this could be a consequence of something that Bob does… even if she has no idea what specifically it could be. But once the hypothesis is there, she can do an experiment; for example mention the plums five times a day, at randomly selected moments, and make notes about Bob’s reactions. Then compare those reactions to a control group (talking about something else).
Not sure if something like this can also be applied to other situations of this kind.
Perhaps Alice might notice that she mysteriously dislikes mentioning plums in Bob’s presence, but not when she is with other people. In that case, she might consider the hypothesis that this could be a consequence of something that Bob does… even if she has no idea what specifically it could be. But once the hypothesis is there, she can do an experiment; for example mention the plums five times a day, at randomly selected moments, and make notes about Bob’s reactions. Then compare those reactions to a control group (talking about something else).
Not sure if something like this can also be applied to other situations of this kind.