There is a certain mood of mind experienced by most of us in which we feel the mystery of existence; in which our consciousness seems to become suddenly separated from our thoughts, and we find ourselves asking, "Who am I? What are these thoughts?" The mood is very apt to overtake us while engaged in the commonest acts. In health it is always momentary, and seems to coincide with the instant of the transition and shift of our attention from one thing to another. It is probably connected with the transfer of energy from one set of faculties to another set, which occurs, for instance, on our waking from sleep, on our hearing a bell at night, on our observing any common object, a chair or a pitcher, at a time when our mind is or has just been thoroughly preoccupied with something else. This displacement of the attention occurs in its most notable form when we walk from the study into the open fields. Nature then attacks us on all sides at once, overwhelms, drowns, and destroys our old thoughts, stimulates vaguely and all at once a thousand new ideas, dissipates all focus of thought and dissolves our attention. If we happen to be mentally fatigued, and we take a walk in the country, a sense of immense relief, of rest and joy, which nothing else on earth can give, accompanies this distraction of the mind from its problems. The reaction fills us with a sense of mystery and expansion. It brings us to the threshold of those spiritual experiences which are the obscure core and reality of our existence, ever alive within us, but generally veiled and sub-conscious. It brings us, as it were, into the ante-chamber of art, poetry, and music. The condition is one of excitation and receptiveness, where art may speak and we shall understand. On the other hand, the condition shows a certain dethronement of the will and attention which may ally it to the hypnotic state.