it should explicitly be stated that the technique of this method is a complex and intricate matter, the acquirement of which is not, as many writers seem over-readily to assume, an easy task, but one requiring much practice, patience and experience. In no branch of science can the testing of the results obtained by the use of an entirely new and difficult technique be satisfactorily submitted to an off-hand trial on the part of some one quite untrained in this, and it is strange that it does not occur to those who do not directly confirm Freud's conclusions as soon as they "try psycho-analysis" that the fact may be due, not, as they hastily infer, to the erroneousness of those conclusions, but to a more humble explanation, namely that they have not mastered the technique. It is at all events striking that up to the present no investigator, in any country, who has taken the trouble to learn the technique of the psycho-analytic method, has reached any conclusions that fail to confirm Freud's in all particulars, although at least fifty thousand dreams have been investigated by this method; this fact in itself speaks for the finished state in which Freud gave the theory to the world.
It is commonly believed in scientific circles that the mental processes of which dreams are composed arise, without any direct psychical antecedent, as the result of irregular excitation of various elements in the cerebral cortex by physiological processes occurring during sleep. This, it is maintained, accounts for the confused and bizarre nature of the mental product, and any apparently logical connection and order that frequently appear to some extent in dreams are explained by the supposition that the mental processes in question are represented in cortical elements that stand in close, anatomical or physiological, relation to one another, and so are simultaneously stimulated by the peripheral stimuli. Hence any problem as to the psychical origin of the mental processes, still more as to the meaning of the dream as a whole, is by the nature of things excluded as being non-existent, and any investigation along such lines is condemned as savouring of antiquated superstitions about the " reading of dreams " unworthy of educated people. To this attitude Freud, as must every consistent philosopher, stands in sharp opposition. He contends that dream processes, like all other mental processes, have their psychical history, that in spite of their peculiar attributes they have a legitimate and comprehensible place in the sequence of mental life, and that their origins can be psychologically traced with as much certainty and precision as those of any other mental processes.
From one point of view dreams may be classified into the following three categories. First may be distinguished those
