Mending Wall
Something there is that doesn’t love a wall,
That sends the frozen-ground-swell under it,
And spills the upper boulders in the sun;
And makes gaps even two can pass abreast.
The work of hunters is another thing:
I have come after them and made repair
Where they have left not one stone on a stone,
But they would have the rabbit out of hiding,
To please the yelping dogs.
....
He will not go behind his father’s saying,
And he likes having thought of it so well
He says again, ‘Good fences make good neighbors.'
Robert Frost, 1874 - 1963
http://www.poets.org/poetsorg/poem/mending-wall