I KNOW the stars by their names,
Aldebaran, Altair,
And I know the path they take
Up heaven's broad blue stair.
I know the secrets of men
By the look of their eyes,
Their gray thoughts, their strange thoughts
Have made me sad and wise.
But your eyes are dark to me
Though they seem to call and call—
I cannot tell if you love me
Or do not love me at all.
I know many things,
But the years come and go,
I shall die not knowing
The thing I long to know.

Sara Teasdale

http://www.poemhunter.com/poem/i-know-the-stars/