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Bishops move diagonally. That’s why they often turn up where the kings don’t expect them to be.
— Terry Pratchett • Small Gods

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The passage turns a chess rule into a joke about unexpected influence. A bishop's diagonal movement becomes a reason for surprising kings. Read beyond the board, the comparison suggests that people who approach power indirectly may arrive where those in charge least expect them.
Context reviewed