In being thus in a certain rapport, though so limited and unintelligent a rapport, with the external world, the mind of the hypnotized patient would appear to be nearer the condition of waking illusion than is the mind of the dreamer.  It must be remembered, however, and this is the second point of difference between dreaming and hypnotism, that the hypnotized subject tends to act out his hallucinations.  His quasi-percepts are wont to transform themselves into actions with a degree of force of which we see no traces in ordinary sleep.  Why there should be this greater activity of the motor organs in the one condition than in the other, seems to be a point as yet unexplained.  All sense-impressions and percepts are doubtless accompanied by some degree of impulse to movement, though, for some reason or another, in natural and healthy sleep these impulses are restricted to the stage of faint nascent stirrings of motor activity which hardly betray themselves externally.  This difference, involving a great difference in the possible practical consequences of the two conditions of natural and hypnotic sleep, clearly serves to bring the latter condition nearer to that of insanity than the former condition is brought.  A strong susceptibility to the hypnotic influence, such as Dr. Heidenhain describes, might, indeed, easily prove a very serious want of “adaptation of internal to external relations,” whereas a tendency to dreaming would hardly prove a maladaptation at all.

CHAPTER VIII.

ILLUSIONS OF INTROSPECTION.

We have now, perhaps, sufficiently reviewed sense-illusions, both of waking life and of sleep.  And having roughly classified them according to their structure and origin, we are ready to go forwards and inquire whether the theory thus reached can be applied to other forms of illusory error.  And here we are compelled to inquire at the outset if anything analogous to sense-illusion is to be found in that other great region of presentative cognition usually marked off from external perception as internal perception, self-reflection, or introspection.

Illusions of Introspection defined.

This inquiry naturally sets out with the question:  What is meant by introspection?  This cannot be better defined, perhaps, than by saying that it is the mind’s immediate reflective cognition of its own states as such.

In one sense, of course, everything we know may be called a mental state, actual or imagined.  Thus, a sense-impression is known, exactly like any other feeling of the mind, as a mental phenomenon or mental modification.  Yet we do not usually speak of introspectively recognizing a sensation.  Our sense-impressions are marked off from all other feelings by having an objective character, that is to say, an immediate relation to the external world, so that in attending to one of them our minds pass away from themselves