When we look at a child, we see that sense of fullness, of intrinsic aliveness, of joy in being, is not the result of something else. There is value in just being oneself, it is not because of something one does or doesn't do. It is there in the beginning, when we are children, but slowly it gets lost.
Enlightenment is construed as seeing things as they really are rather than as they appear; it is a direct insight into, and discernment of, the nature of reality that is apprehended only by wisdom, which transcends and is prior to the activity of discriminative thought. In this view, delusion is defined as all that is opposed to enlightenment.