Blake's Innocent --
A person who believes that this is the "best of all possible worlds." Acceptance of this doctrine is a form of ignorance and blindness which makes one incapable of "seeing" that the world might be made better or using one's imagination to construct a better, more just world. Innocent beings -- lambs, children, middle class women, ignorant peasants, and wealthy capitalists or aristocrats -- are among such blind and helpless types in Blake's poetry.
Blake's "Infant Joy" succinctly expresses this state of mind and being.