of the laws of thought and will the human intellect is led astray in dreams by confusing one notion with another. Thus it happens that in dreams we formulate and commit the greatest of contradictions, while, on the other hand, we display the shrewdest judgment and arrive at the most logical conclusions, and are able to make the most virtuous and sacred resolutions. The lack of orientation is the whole secret of our flights of phantasy in dreams, and the lack of critical reflection and agreement with other minds is the main source of the reckless extravagances of our judgments, hopes and wishes in dreams" (p. 18).

If the turning-away from the outer world is accepted as the decisive cause of the most conspicuous characteristics of our dreams, it will be worth our while to consider certain subtle observations of Burdach's, which will throw some light on the relation of the sleeping psyche to the outer world, and at the same time serve to prevent our over-estimating the importance of the above deductions. "Sleep," says Burdach, "results only under the condition that the mind is not excited by sensory stimuli... yet it is not so much a lack of sensory stimuli that conditions sleep as a lack of interest in them; * some sensory impressions are even necessary in so far as they serve to calm the mind; thus the miller can fall asleep only when he hears the clatter of his mill, and he who finds it necessary, as a matter of precaution, to burn a light at night, cannot fall asleep in the dark" (p. 457).

* Compare with this the element of "Desinteret," in which Claparede (1905) finds the mechanism of falling asleep.

"During sleep the psyche isolates itself from the outer world, and withdraws from the periphery.... Nevertheless, the connection is not entirely broken; if one did not hear and feel during sleep, but only after waking, one would assuredly never be awakened at all. The continuance of sensation is even more plainly shown by the fact that we are not always awakened by the mere force of the sensory impression, but by its relation to the psyche. An indifferent word does not arouse the sleeper, but if called by name he wakes... so that even in sleep the psyche discriminates between sensations.... Hence one may even be awakened by the obliteration of a sensory stimulus, if this is related to anything of imagined importance. Thus one man wakes when the nightlight is extinguished, and the miller when his mill comes to a standstill; that is, waking is due to the cessation of a sensory activity, and this presupposes that the activity has been perceived, but has not disturbed the mind, its effect being indifferent, or actually reassuring" (p. 46, etc.).

Even if we are willing to disregard these by no means trifling objections, we must yet admit that the qualities of dream-life hitherto considered, which are attributed to withdrawal from the outer world, cannot fully account for the strangeness of dreams. For otherwise it would be possible to reconvert the hallucinations of the dream into mental images, and the situations of the dream into thoughts, and thus to achieve the task of dream-interpretation. Now this is precisely what we do when we reproduce a dream from memory after waking, and no matter whether we are fully or only partially successful in this retranslation, the dream still remains as mysterious as before.

Furthermore, all writers unhesitatingly assume that still other and profounder changes take place in the plastic material of waking life. Strumpell seeks to isolate one of these changes as follows: (p. 17) "With the cessation of active sensory perception and of normal consciousness, the psyche is deprived of the soil in which its feelings, desires, interests, and activities are rooted. Those psychic states, feelings, interests, and valuations, which in the waking state adhere to memory-images, succumb to an obscuring pressure, in consequence of which their connection with these images is severed; the perceptual images of things, persons, localities, events and actions of the waking state are, individually, abundantly reproduced, but none of these brings with it its psychic value. Deprived of this, they hover in the mind dependent on their own resources..."

This annihilation of psychic values, which is in turn referred to a turning away from the outer world, is, according to Strumpell, very largely responsible for the impression of strangeness with which the dream is coloured in our memory.