hindrances to sleep. Every one knows the charming story of the bad boy (Baldwin Groller's) who awoke at night bellowing out, “I want the rhinoceros.” A really good boy, instead of bellowing, would have dreamt that he was playing with the rhinoceros. Because the dream which realizes his desire is believed during sleep, it removes the desire and makes sleep possible. It cannot be denied that this belief accords with the dream image, because it is arrayed in the psychical appearance of probability; the child is without the capacity which it will acquire later to distinguish hallucinations or phantasies from reality.

The adult has learnt this differentiation; he has also learnt the futility of desire, and by continuous practice manages to postpone his aspirations, until they can be granted in some