Being

GKC:

There is at the back of all our lives an abyss of light, more blinding and unfathomable than any abyss of darkness; and it is the abyss of actuality, of existence, of the fact that things truly are, and that we ourselves are incredibly and sometimes almost incredulously real. It is the fundamental fact of being, as against not being; it is unthinkable, yet we cannot unthink it, though we may sometimes be unthinking about it; unthinking and especially unthanking. For he who has realized this reality knows that it does outweigh, literally to infinity, all lesser regrets or arguments for negation, and that under all our grumblings there is a subconscious substance of gratitude. ....

G.K. Chesterton, Chaucer, found in The Quotable Chesterton, Ignatius Press, 1986.