The feeling of bliss accompanies all those moments when one feels borne along by the current of life, when what was dammed up can flow off without restraint, when there is no need to do this thing or that thing with a conscious effort in order to find a way out or to achieve a result. We have all known situations or moods when things go of themselves, when we no longer need to manufacture all sorts of wearisome conditions for our joy or pleasure. The time of childhood is the unforgettable emblem of this joy, which, unperturbed by things without, pours in a warm flood from within. Childlikeness is therefore a symbol of that unique inner condition on which blissfulness depends. To be like a child means to possess a treasury of accumulated libido which can constantly stream forth. The libido of the child flows into things; in this way he gains the world, then by degrees loses himself in the world through gradual over-valuation of things.

Psychological Types by Carl Gustav Jung