Take this kiss upon the brow!
And, in parting from you now,
Thus much let me avow-
You are not wrong, who deem
That my days have been a dream;
Yet if hope has flown away
In a night, or in a day,
In a vision, or in none,
Is it therefore the less gone?
All that we see or seem
Is but a dream within a dream.

I stand amid the roar
Of a surf-tormented shore,
And I hold within my hand
Grains of the golden sand-
How few! yet how they creep
Through my fingers to the deep,
While I weep- while I weep!
O God! can I not grasp
Them with a tighter clasp?
O God! can I not save
One from the pitiless wave?
Is all that we see or seem
But a dream within a dream?

(Edgar Allan Poe)

The second stanza has some stark and pathetic imagery. The desperate man clutches at sand as it falls away; he does not weep and cling to the sand for the sand’s sake, it’s simply keeping him from that “sea” of death.

But I wonder what–within those lines there–what caused him to suddenly question his conviction of all being a “dream within a dream”? He certainly seemed sure enough about what he saw as the false nature of life before he saw his own life slipping away… Perhaps it was that he saw death; he saw life’s opposite, and then realized that life is not a dream. After all, how do we know what hot is without cold? And what dream has an opposite? Do we “wake” in death?