It describes the poet's musings on death over a series of nine "nights" in which he ponders the loss of his wife and friends, and laments human frailties.
The best-known line in the poem (at the end of "Night I") is the adage "procrastination is the thief of time", which is part of a passage in which the poet discusses how quickly life and opportunities can slip away.
In his 1791 book, Life of Samuel Johnson, James Boswell called Night-Thoughts "the grandest and richest poetry that human genius has ever produced".
William Blake was commissioned in 1795 to illustrate Night-Thoughts for a major new edition of the poem to be published by Richard Edwards.
[1] In 2005, the Folio Society published in two volumes a fine edition facsimile accompanied by a commentary by Robyn Hamlyn.