Think thou and act; to-morrow thou shalt die.
Outstretch’d in the sun’s warmth upon the shore,
Thou say’st: ‘Man’s measured path is all gone o’er:
Up all his years, steeply, with strain and sigh,
Man clomb until he touch’d the truth; and I,
Even I, am he whom it was destined for.’
How should this be? Art thou then so much more
Than they who sow’d, that thou shouldst reap thereby?
Nay, come up hither. From this wave-wash’d mound
Unto the furthest flood-brim look with me;
Then reach on with thy thought till it be drown’d.
Miles and miles distant though the last line be,
And though thy soul sail leagues and leagues beyond,—
Still, leagues beyond those leagues, there is more sea.
Dante Gabriel Rossetti
http://www.poemhunter.com/poem/the-choice-4/