Sentence:  If the photographically realistic continuity of dreams , however bizarre their combinations , denies that it is purely a composition of the <WSD>brain</WSD> , it must be compounded from views of diverse realities , although some of them may never be encountered in what we are pleased to call the real life . 
Meaning of the word marked with <WSD> tags:  that part of the central nervous system that includes all the higher nervous centers; enclosed within the skull; continuous with the spinal cord