In the ancient Greek conception of “the underworld,” the shades that dwell there are individual souls still, as they were in the world above. They are still cut off from the unknown, unknowable, and universal “fate” that determines the outcomes of human actions, and which brought each one of them to this place. Hegel describes the ancient belief in “the nothingness of necessity”: there is such a thing as fate, but it is dark and mysterious, something the human mind could know nothing about, even if it searched and wondered for an eternity. From a human perspective, then, fate is nothing, nothing can be said about it, and yet it determines everything.
The later concept of “Heaven” develops out of and in contrast to the ancient visions of the underworld. Whereas ancient souls would continue, after death, to wander in the dark, still disconnected from the universal power of fate, in Heaven it is different: the soul is no longer merely individual, but is reunited, after death, with the universal, with God, thereby becoming “clear to itself.” In Heaven, the soul comes to know the power that had been guiding it all of its life.
The Enlightenment, since it has reason as its foundation, is opposed to this view of Heaven: as we’ve seen, reason has no interest in anything beyond this world, and the soul finds all the satisfaction it needs in the here and now.
Out of the Enlightenment comes what Hegel calls “morality,” which is a form of consciousness that is certain of itself. Morality, or the moral self-consciousness, has the universal within itself, and so it can be clear to itself here, in life. Morality is certain that it lives its life correctly because it believes it finds the universal within itself.
This, at least, is the belief that morality clings to, certain that it no longer has any need for the old-fashioned concepts of fate, Heaven, or Hell.
(I’ve been reading A.V. Miller’s translation of Hegel’s Phenomenology of Spirit.)