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And somewhere on this good boffo stretch of coastline lay the house of this inconsolable man, a man whom many regarded as being insane. But this was only, as he would tell people, because he was.
— Douglas Adams · So Long, and Thanks For All the Fish

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The narrator introduces a deeply unhappy man whom others consider insane, then reports his blunt agreement with them. The expected defence never arrives. That reversal turns an explanation of other people's judgment into a dry admission, giving the description its compact, self-confirming joke.
Context reviewed