We can think of the Unconscious as a tide which ebbs and flows. In sleep it seems to submerge the conscious altogether, while at our moments of full wakefulness, when the attention and will are both at work, the tide is at its lowest ebb. Between these two extremes are any number of intermediary levels. When we are drowsy, dreamy, lulled into a gentle reverie by music or by a picture or a poem, the Unconscious tide is high; the more wakeful and alert we become the lower it sinks. This submersion of the conscious mind is called by Baudouin the "Outcropping of the Subconscious." The highest degree of outcropping, compatible with the conscious direction of our thoughts, occurs just before we fall asleep and just after we wake. It is fairly obvious that the greater the outcropping the more accessible these dynamic strata of the mind become, and the easier it is to implant there any idea we wish to realise. As the Unconscious tide rises the active levels of the mind are overflowed; thought is released from its task of serving our conscious aims in the real world of matter, and moves among the more primal wishes and desires which people the Unconscious, like a diver walking the strange world beneath the sea. But the laws by which thought is governed on this sub-surface level are not those of our ordinary waking consciousness. During outcropping association by contraries does not seem readily to take place. Thus the mal-association, which neutralised the desired idea and so prevented acceptation, no longer presents itself. We all know what happens during a "day-dream" or "brown-study," when the Unconscious tide is high. A succession of bright images glides smoothly through the mind. The original thought spins itself on and on; no obstacles seem to stop it, no questions of probability arise; we are cut off from the actual conditions of life and live in a world where all things are possible. These day-dreams cause very potent autosuggestions, and one should take care that they are wholesome and innocent; but the important point is that on this level of consciousness association seems to operate by similarity, and emotion is comparatively intense. These conditions are highly favourable to acceptation.