Lyric discussion by nerdynurse 

It's most likely about the class structure and rising through the ranks. All of the things that Neil is talking about are indicators of the upper class in England.

Assuming the Perpendicular being the rising up through the ranks from lower or middle class to the world of Berber jackets, libraries with wheeled ladders and grand country seats with grounds as designed by Capability Brown.

It makes me think of Evelyn Waugh and his bright young things idly playing around in a world of privilege with ridiculous names like Lavinia.

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