The "opening of centers" William Blake has taken from Jacob Boehme, employing, as he so often does, a symbol that cannot be fully understood unless we turn to its original author. The rainbow for Blake and Boehme, on the other hand, is the symbol of the "Opening" of the eternal world into manifestation, and therefore of the Last Judgment. The "Wild Thyme" is perhaps a pun; it is the wild time, the secret moment, that Blake means-the inspired, "wild" moment "that Satan cannot find." Blake's The Fly is a significant reversal of a commonplace image of the minuteness and insignificance of men, used by Gray in a poem that Blake had illustrated in the early 1790s. For Blake flowers, worm, and fly are symbols both of the significance of even the smallest living creature and of the punctum itself, alike present in the least and in the greatest.