If they be two, they are two so
As stiff twin compasses are two;
Thy soul, the fix'd foot, makes no show
To move, but doth, if th' other do.

And though it in the centre sit,
Yet, when the other far doth roam,
It leans, and hearkens after it,
And grows erect, as that comes home.

Such wilt thou be to me, who must,
Like th' other foot, obliquely run;
Thy firmness makes my circle just,
And makes me end where I begun.



(from John Donne's A Valediction: forbidding mourning)