Two Boats at Flat Rock

Why do I see these empty boats, sailing on airy seas? 
One haunted me the whole night long, swaying with every breeze, 
Returning always near the eaves, or by the skylight glass: 
There it will wait me many weeks, and then, at last, will pass. 
Each soul is haunted by a ship in which that soul might ride 
And climb the glorious mysteries of Heaven's silent tide 
In voyages that change the very metes and bounds of Fate — 
O empty boats, we all refuse, that by our windows wait!

- Vachel Lindsay