Pensive, at eve, on the hard world I mused,
And my poor heart was sad: so at the Moon
I gazed--and sighed, and sighed--for, ah! how soon
Eve saddens into night! Mine eyes perused,
With tearful vacancy, the dampy grass,
That wept and glitter'd in the paly ray,
And I did pause me on my lonely way,
And mused me on the wretched ones, who pass
O'er the black heath of Sorrow. But, alas!
Most of myself I thought: when it befell,
That the sooth Spirit of the breezy wood
Breath'd in mine ear--'All this is very well;
But much of one thing is for no thing good.'
Ah! my poor heart's inexplicable swell!

Samuel Taylor Coleridge

http://www.poemhunter.com/poem/sonnet-xxi-4/