The sublime is a concept in romantic poetry that applies to the description of nature and how man comprehends the realm of experience that cannot be easily defined or measured. The sublime in Romantic poetry therefore applies to the way that contemplating nature heightens man's understanding of himself and the world and his place in it. Shelley was a Romantic poet whose understanding of the sublime was quite dark, as his poems paint a picture of nature as being powerful and ruthless, exposing the frailty of man and man's lack of power. Consider, for example, how this view is expressed through the presentation of nature in "Ode to the West Wind":
The sea-blooms and the oozy woods which wear
The sapless foliage of the ocean, know
Thy voice, and suddenly grow grey with fear
And tremble and despoil themselves--O hear!
The West Wind is described in terms that emphasise its power and majesty, making even other parts of nature "grow grey with fear" at its arrival. The sublime, or transcendent experience, is thus described in a way that highlights man's place in the world as being subject to such natural forces and recognising his own frailty. Note how this is also picked up in "Ozymandias":
Nothing beside remains: round the decay
Of that colossal wreck, boundless and bare,
The lone and level sands stretch far away.
Again, nature is presented as an infinitely powerful entity who has the ability to wipe out and erase entire civilisations through its might. Part of the sublime therefore is understanding how in nature Shelley saw reflected mankind's ephemeral existence and limited role in the world. The might and majesty of nature as presented in his work points towards man's lack of power and inherent fragility when faced with the might of nature.