Lucid Dreams

            
             A person may realize that he or she is dreaming while still in the dream state. Such dreams have been called Dreams of Knowledge by Oliver Fox (1962). Paul Tholey, a German psychologist who first began to study conscious dreaming in 1959, called the phenomena Klartraum, a German word meaning "clear dream". These dream experiences, however, are more commonly known as "lucid dreams", a term first introduced by van Eeden (1913). References to lucid dreaming date back at least to the time of Aristotle, and have appeared in a variety of contexts, ranging from a letter written in A.D. 415 by St. Augustine, to the writings of Friedrich Nietzche, and ancient Tibetan Buddhist texts (Gillespie, 1988; LaBerge, 1985). Though several works on the phenomenon appeared in the 19th and early 20th century (e.g., Arnold-Forster, 1921; Brown, 1936; Saint-Denys, 1982/1867; van Eeden, 1913), it is really only in the past decade that lucid dreaming has become the subject of scientific inquiry. .
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             Definitions of Lucid Dreaming.
             What exactly is a lucid dream? Various definitions of the experience have emerged in the literature. The simplest of these states that lucid dreams are those in which the subject is aware that he or she is dreaming (e.g., Green, 1968). It is this basic definition which appears most frequently. Other researchers, such as Hearne (1981; 1987), have added a qualifier: that one has to become perfectly or fully aware that one is dreaming. Exactly what is meant by the terms "perfectly" or "fully" is not explicitly stated, but it appears that Hearne considers the ability to consciously exert control over events in the dream scenery to be an important aspect of dream lucidity. It should be noted, however, that even though lucidity in dreams is often accompanied by varying degrees of dream control, this ability is not in itself a sufficient indicator of lucidity. This point is clearly made by Tart (1988) and is evident in one of the case studies presented at the end of the thesis.