What author gave this illustration of truth via a backyard fence? Long ago I was told a story, which is now probably corrupted in my mind, that makes a good illustration of the relationship between rules and freedom in Christianity.

It goes something like this: a family's house has a backyard that ends in a cliff. The child, playing in the backyard, is afraid of the cliff, and therefore stays near the house. However, when a fence (think "rules") is erected around the perimeter of the backyard, the child experiences freedom to play throughout the whole yard. Moral: the truth can set us free.

I originally thought that this story was owed to C. S. Lewis, but now I cannot track it down. Who authored this idea?
G.K. Chesterton in his seminal work Orthodoxy:


  Those countries in Europe which are still influenced by priests, are exactly the countries where there is still singing and dancing and coloured dresses and art in the open-air. Catholic doctrine and discipline may be walls; but they are the walls of a playground. Christianity is the only frame which has preserved the pleasure of Paganism. We might fancy some children playing on the flat grassy top of some tall island in the sea. So long as there was a wall round the cliff's edge they could fling themselves into every frantic game and make the place the noisiest of nurseries. But the walls were knocked down, leaving the naked peril of the precipice. They did not fall over; but when their friends returned to them they were all huddled in terror in the centre of the island; and their song had ceased.


He's pretty much saying that Orthodoxy leaves a person free'er to be truly human and truly alive than breaking laws and smashing things or being a pagan would leave you.  

Note, Chesterton says "Catholic Doctrine" here, but this was written many years before he, himself, entered the Catholic Church.


Read it on Gutenberg
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