242 MYTH AND SCIENCE. 



of images seen in dreams, as well as in those which 

 appear in illusions, in normal hallucinations of the 

 senses, and in those which are abnormal, in ecstasy, 

 in delirium, in madness, in idiocy, and dementia. 

 In all these mental conditions, we ascribe a body 

 and material existence to images which for various 

 causes appear to be really presented to our senses. 



If we are able to show that all such appearances 

 are believed to have a real existence in virtue of the 

 same law and faculty of perception which generated 

 myth in its earliest manifestation, we shall have 

 succeeded in establishing a common genesis for all 

 these various psychical phenomena, thus affording no 

 contemptible contribution to psychology in general, 

 and to the science of human thought. 



To dream is not merely a normal act of man, but, 

 as it appears from many witnesses, it is common to 

 all animals. In dreams the ordinary laws of time 

 and space are strangely modified, and images of all 

 kinds appear, sometimes confusedly, sometimes in a 

 rational order, often in accordance with the laws of 

 association, while the voluntary exercise of thought 

 may . be said to be dormant. This is, speaking 

 generally, the condition and nature of dreams, which 

 we must presently consider adequately with more 

 subtle and exact analysis. 



Before we trace the cause of the apparent reality 

 of these images, and the laws which govern it, let us 

 consider man in his waking condition, so as to 



