His basic principle was the broken-window theory: If you don't fix one window in the building, another will be broken and then another, and eventually the whole block will be lost.

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In this case, the "seen" was a shopkeeper's broken window that would create economic growth for the shopkeeper hiring a glazier to replace the window, with the glazier spending the money earned elsewhere.

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Geoffrey de cided to place an old, slightly exotic-looking, artistically shaped radiator, which he had removed for a client because it was broken, in the window of his workshop, just to make it look like a shop.

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Most famously, if one window was broken in a building and left unrepaired (his italics), soon all the other windows would be broken too, and criminal elements would take over.

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