As in other countries there were various reports of lucid dreams recorded through the centuries by German philosophers, poets and occultists. But these, as well as the investigations carried out by serious researchers, were completely ignored by scientists because they were based on personal experiences (see SCHRIEVER, 1935; MOERS-MESSMER, 1939). It was not until 1959 at Johann Wolfgang Goethe University that an effective technique for inducing lucid dreams was developed and the first systematic investigations involving several subjects took place. In this article I will discuss the beginnings of this research as well as its further development. Aside from the purely chronological ordering of the individual steps of the development of the research, I would also like to provide a basic outline of the inner connections of the particular areas within the overall research program. This will require analyzing the development of individual branches of research abstracted from their actual chronological order.
In Figure 1 the important areas of lucid dream research in their chronological and logical contexts are summarized. Clearly not all individual branches can be listed and many spheres can only be sketched. Those points which I already pub-lished in English will receive only brief mention. In this connection, I would like to point out that a much briefer version of this overview appeared in Lucidity Letter in June, 1988 (THOLEY, 1988c). Unfortunately, only the first part of a more comprehensive abstract was translated and published at that time and more recent research was entirely omitted. Here I would like to speak to some of the research themes not mentioned at that time and especially to highlight two of the more current and somewhat related focal points of investigation: the different forms of lucidity and non-ordinary ego-experiences.
First, I would like to treat in some detail the critical realistic model of the
per-ceptual world, given its fundamental significance to the development of our
lucid dream research program and the interpretation and application of our findings
(see also THOLEY, 1986b). This model postulates a distinction between the physical
world (physical body and physical environment) and the phenomenal world (phenomenal
body ego and phenomenal environment). In the waking state, the physical world is
representedùmore or less accuratelyùby sensory and memory processes
in the brain. This was illustrated in a somewhat simplified way in the example of
perception in my 1986(b) article (p. 45). It was a simplification because I did
not make a strict distinction between the phenomenal facts and the brain correlates.
In fact, we are inclined to adopt a view of psychophysical identity, isomorphism
or parallelism. This is not a purely philosophical question, rather, it is a matter
of working hypotheses which can be subjected to empirical testing and are not dependent
on exact phenomenal/brain distinctions (for details see THOLEY, 1980a; 1989c).
We most emphatically distinguish ourselves, however, from naïve-realistic
conceptions (e.g., GIBSON, 1979) and from the idealistic and similar radical constructivist
conceptions. The radical constructivists confuse the critical-phenomenal conception
of the physical world with the physical world itself. The former is constructed
on the basis of perception and thought, and frequently changes; whereas the latter
obeys unchanging natural laws. A naïve-realistic model has especially negative
consequences with respect to research and practice in the field of lucid dreaming
and the related field of out-of-body experiences (OBEs). It not only hampers research,
but for people who misinterpret such experiences it can have very dangerous consequences,
possibly leading to serious mental disorders.
Just as the perceived world can provide us with information about physical reality
despite the many deceptions and illusions, the dream world can present us with information
about our psychological reality (the psychological person and his or her psychological
situation), despite symbolic distortions. In general, we take the term "reality"
to mean simply anything that has an effect. Accordingly, we understand psychological
reality to mean the totality of that which can have an effect on our experience
and behavior (see LEWIN, 1936). This would especially include the so-called unconscious
facts which we can conceptualize as psychological constructs and which can basically
be replaced by physiological concepts at a later time.
Here we are in agreement with FREUD that dreams are the "royal road"
to the unconscious. But this is of little help when, in the orthodox psychoanalytic
sense, normal dreams are experienced with a hazy consciousness and the absence of
an ability to act. Or after waking when we report to a biased psychotherapist about
our even more hazy and distorted observations and the associations connected to
In order to gain insight into our psychological problems and resolve them, it
is much more important to interact with the symbolic world in a way enabled by lucid
consciousness and the consequent greater freedom of action. Just as we can interact
with physical reality in a waking state by means of the sensory-motor feedback system,
we are capable of taking action in the psychological reality of lucid dreams due
to the reciprocal reactions between the symbolic events and the underlying psychological
processes. These fundamental principles have provided the basic underpinnings guiding
our investigations into lucid dreaming. The results of the research have shown them
to be extremely sound in practice.
But now let us turn to the epistemological considerations described in the article written for Lucidity Letter in 1986, in which I focused exclusively on the process of perception. I also emphasized that it was an understanding of the critical realistic model which first brought me to the idea of developing a method for inducing lucid dreams, a method I will only briefly describe.
The Reflection Technique
When I recognized that the objective - and intersubjective -appearing perceptual
world was merely a phenomenal world, it occurred to me to compare this phenomenal
waking world with the dream world through systematic observation. The dream world
is, in fact, a phenomenal world. But, being less dependent on sensory stimulation,
it is possible for events to transpire which are not possible with normal perception
in a waking state. Such unusual events made it possible for me to recognize the
On the basis of these ideas, I developed my first technique for inducing lucid
dreams in 1959. I called it the "Reflection Technique." Using this technique,
the subject asks him or herself several times during the course of the day: "Am
I awake, or am I dreaming?" The purpose is to achieve a generally critical
attitude towards one's state of consciousness. When confronted with unusual experiences,
this facilitates recognition of the dreaming state.
After four weeks I had my first lucid dream. I recognized that I was dreaming
because I saw an aunt whom I knew to have been dead for some time. Since I was not
at all acquainted with such phenomena at that time, I was at first fascinated by
this new experience. Later, however, I was seized by a kind of claustrophobic feeling
because I did not know how or whether I would be able to get out of this dream world.
I finally woke up after staring at a flower in the dream environment until the flower
and the entire surroundings became blurred.
PRICE and COHEN (1988), who refer to only one of my articles translated into
English, have referred to the reflection technique as the development of an active
attitude. With respect to the early application of the technique this is correct.
A process of active questioning, however, ultimately gives rise to a passively receptive
focus on current experience which, in turn, makes the posing of critical questions
a superfluous matter. In other words, increased practice helps develop the disposition
making it possible to recognize the dreaming state when triggered by unusual events.
A first important goal in improving the effectiveness of the reflection technique
was finding the appropriate criteria for recognizing the dreaming state. These criteria
make it possible to spontaneously recognize that one is dreaming: particularities
of dreamlike perception and/or the contradiction between knowledge of events in
a waking state and momentarily experienced dream events. It is also possible to
test whether one is awake or dreaming through a series of physical and mental activities.
For example, the subject turns himself approximately 180 degrees and then attempts
to stand still. In a dream state, as a rule, the body continues to turn in the same
direction or the surroundings begin to revolve in the opposite direction. However,
the subject may hesitate to conduct such a test in the presence of other people
because of the possibility that he/she is awake. After all most of us shy away from
carrying out such unusual activities in front of potential onlookers. Thus mental
tests may be preferable.
One of the most effective tests is trying to remember what has happened during
the immediately preceding period of time. Should one experience bizarre events or
a lapse of memory, this may indicate that one is dreaming. However, this test is
useless if the subject wakes up, since it could be a "false awakening."
Therefore, turning a light on, for example, is recommended upon waking up. If the
light does not go on, this may signify a dream state.
We have found countless examples that suggest the apparent existence of various
forms of psychological resistance which appear to hinder or prematurely end dream
lucidity (THOLEY, 1981; 1988b).
For instance during one of my own dreams I saw houses, trees and other objects all standing upside down. I immediately thought that I was dreaming. Shortly thereafter it seemed as if I had a pair of glasses on. It occurred to me that the glasses might have been equipped with reversing lenses such as those used in psychological experiments dealing with perception. When I proceeded to take off the glasses I saw my surroundings in a normal, upright position and I no longer believed I was dreaming. We have collected hundreds of such examples suggesting that various forms of psychological resistance apparently seek to hinder lucidity during dreaming.
The Expansion of the Lucid Dream Induction Technique
The expansion of the original reflection technique, resulting in the combined
technique, was accomplished by incorporating elements of intention and auto-suggestion
(THOLEY, 1982; 1983b). Several researchers outside of our group have shown the effectiveness
of our methods (BOUCHET & RIPERT, 1986; LEVITAN, 1989). Relatedly, a new combined
technique developed by KLIPPSTEIN (1988) should also be mentioned. We have recently
attempted to isolate and investigate the effec-tiveness of certain factors within
the overall technique (UTECHT, 1987; SCHLAG, in preparation).
To understand the further development of our induction technique, it is important
to point out that the actual clarity about one's state of consciousness is not by
itself a sufficient criterion for defining a lucid dream. Additional factors also
have to be distinguished. To illustrate this we have listed six different criteria
in Table 1 which are not only relevant to the dream state, but (all other conditions
being equal) also to the waking state and various intermediate states as wellùabove
all, the "state of imagery." Consequently, during the further development
of our induction technique, we have placed a high value on practicing as many aspects
of lucidity as possible during the waking state so that they will be ready for application
in the dream state.
Next we want to bring to the readers attention the second criterion of lucidity,
"lucidity about individual freedom in decision and action." We consider
this aspect to be especially important because it is indispensable for experimentation
in lucid dreaming and because the fulfillment of this criterion completely changes
the quality of the dream. That is with the second aspect the other aspects of lucidity
simultaneously appear, with the exception of the sixth aspect. The sixth aspect
of lucidity can be practiced more easily in a "state of imagery" or in
a state of waking fantasy (see also MALAMUD, 1979) than in a waking state, which
is usually characterized by a lack of symbolic facts.
Our techniques are somewhat aimed at the same goal as Charles TART in his book
Waking Up (1986). TART's book is based on the teachings of GURDJIEFF and
assumes the validity of the hypothesis found in many older spiritual teachings that
we are in a kind of psychological sleep or dream state, even during our waking hours.
In metaphorical terms, TART says that we have to pull up the weeds (transform unconsciousness
into consciousness) in order to be able to enjoy the flowers. The techniques described
by him are in reference to the waking state and include some which are similar to
our methods (e.g., "self-observation" and "self-remembering").
Our method, however, is more involved. As noted, we also begin with waking techniques. But, we want to arrive at lucidity in a dream state as quickly as possible because it is there that we can come face to face with TART's "weeds" in unadulterated forms. In this way we can directly confront the unconscious and thus free our-selves from it by a continuous feedback processes. Eventually, we hope to reach ever higher levels of lucidity in various states of consciousness.
Since, according to the critical realistic model, the phenomenal (waking or dream)
world is the only immediately accessible world, empirical phenomenology (in the
sense of the observation and description of phenomena) is indispensable for all
sciences. The criteria of objectivity and intersubjectivity, which are often used
to characterize a science, cannot be maintained, in a strict sense, by the critical
realists because they can ultimately be established only through subjective means
and thus one can be fundamentally in error. This can be confirmed by anyone who
has considered himself to be in a waking state, while, in fact, he was dreaming.
This is because the world in a dream state can have the same objective and intersubjective
appearance as in a waking state. The possibility of making such a fundamental error,
however, does not mean that we have to adopt a completely skeptical position. Conviction
does not always lead to objectively and intersubjectively valid observations, but
it does so as a rule. Given that empirical phenomenology, by definition, does not
seek to investigate objective facts, we demand only intersubjectivity as a criterion
for something's scientific character. Indeed, no single particular fact can be tested
(e.g., that someone has dreamed in color at a particular time). But more general
facts, such as the actual occurrence of dreaming in color, for example, can be subjected
to testing (for details see THOLEY, 1980b).
Experimental phenomenology was the basic and most often used method in our lucid
dream research (for details see THOLEY, 1986a). With this method, the researcher
instructs the subjects or groups of subjects to carry out various specific activities
during lucid dreaming, to observe their effects and record their observations independently
of each other immediately upon awakening. For judging the subjects' memory capabilities,
it is important that they remember not only immediate phenomenal facts, but also
the conclusions and judgements made about these facts (see THOLEY, 1981). An interview
technique developed by REIS (1989b), which is based on a detailed recording of dream
experiences, allows for even more reliable and valid information on dream content
than one normally finds with the usual analyti-cal methods. With the help of phenomenological
experiments, it is possible to test psychological hypotheses about functional dependencies
on phenomenal facts, as well as psychophysiological hypotheses about the relationships
between phenomenal and physiological facts.
Objections to the control of dreams have recently emerged in the lucid dream literature. To these objections we can only reply that in our research and clinical work, we have obtained numerous results through the control of dreams making it possible for us to help many people. The subjects of pilot studies always participate voluntarily in our investigations and were always made aware of potential dangers. It is also understandable that the content of our subjects' lucid dreams would differ extensively from the reports of spontaneous lucid dreamers. Above all, our experimental-phenomenological findings are distinguished from the results obtained by an analysis of spontaneous lucid dreams by a significantly greater diver-sity of experiential possibilities.
In these experiments we tested a vast number of hypotheses in the area of per-ception
and cognition during lucid dreaming which I have lectured on in detail since 1973
and which, in part, are only to be found in the unpublished reports and dissertations
of my students. From among my German publications, I would highlight my review article
The phenomenological experiments on perception were first modeled on the usual
perceptual experiments in the waking state. We determined if double images, after
images and reversible phenomena appeared during lucid dreams under appro-priate
conditions. These experiments also helped in identifying criterion for distin-guishing
between a waking and a dream state (see above). We found that all of these phenomena
were sometimes, if not always, observed. Although we can frequently recognize the
fact that we are dreaming, thirty years of research has still not given us an absolutely
reliable test for determining this. This applies especially to the most effective
dream criteria discussed earlier.
During lucid dreaming we can sometimes consciously produce perceptual phenomena
which differ completely from perception in a waking state - for example, a panoramic
field of vision extending 360 degrees in both horizontal and vertical directions.
In general, this has occurred only when the dream-ego was in an asomatic or disembodied
state (see below). We also succeeded in deliberately defying gravity and slowing
down or speeding up time through the use of various techniques (see THOLEY &
In the area of memory, we discovered that subjects in a lucid dream state could
not only remember their waking state but also their previous dreams. We were able
to establish this by comparing the notes recorded after their earlier dreams. The
latter is most assuredly connected to the problem of state-specific memory. Long-term
memory appears to function somewhat better than short-term memory during lucid dreaming.
In the sphere of logical thinking, we found that the dream-ego was capable of
solving double-digit multiplication tasks. In addition, some subjects were able
to solve problems of logic which they had unsuccessfully attempted prior to going
to sleep. Artistic creative ability was also shown in varying areas, especially
during hypnagogic dream phases (LIRZER, 1981).
The abilities of other dream characters were also examined in a way similar to the abilities of the dream-ego. We saw that the cognitive and artistic performance of other dream figures equaled or surpassed that of the dream-ego, but were less capable of solving arithmetic problems (KRIST, 1981; THOLEY, 1985; 1989a).
We devoted a great deal of attention to the "internal" (emotional and
motivational) and "external" (verbal and behavioral) activities of the
dream-ego during interaction with other dream figures (THOLEY, 1981; 1982; 1984;
1988b). We found that in general, positive effects on both the dream and waking
life of the dreamer accompanied interactions of a peaceful nature. With regard to
this, we mainly want to make some comments which supplement already published material
(see especially the English article, THOLEY, 1988b).
We have indicated that some of the dream characters form sub-systems of the personality.
Even though exact distinctions are not necessarily possible, these sub-systems can
be of a more inner-personal or psycho-social nature, on the one hand, or of a more
habitual or immediate nature, on the other. We have previously pointed out that
dream characters can be altered through changes in our emotional attitude and that
we can even create other dream characters.
For example, when I am angry or afraid in a dream, I can blow out the anger or
fear through my mouth and thereby create a dream character which takes on an appearance
corresponding to the emotion. An indirect way of creating dream charac-ters consists
in taking certain actions which trigger strong emotions, such as a guilty conscience.
Aggressive actions in dreams are frequently met with punishment meted out by avenging
figures. One of my own dreams illustrates this:
I knocked down a dream figure in an enclosed room in order to see if I would be punished. I was seized by the feeling that I would be confronted with something unpleasant, as had happened in previous cases. Tense, but calm, I waited a moment. But nothing happened. Inwardly triumphant, I then wanted to leave the room. There, before the door, stood a huge person with a hood over his head who immediately lunged at me causing [me] great fear.
Whether such figures appear or not (above all, in response to socially taboo
actions of an aggressive or sexual nature), varies from subject to subject. This
seems to offer proof that the appearance and possible changes of the other dream
characters is dependent on the dreamer's current emotional state, while this emotional
state, however, is dependent on the habitual attitudes or sub-systems of the personality.
Learning processes probably play a large role in communication with other dream characters. Inexperienced lucid dreamers frequently have difficulty conducting a rational dialogue with other dream figures. This is because most of these figures play word games involving hidden or multiple meanings which the dream-ego can not initially understand. Thus, it is not surprising that the dream-ego considers the other dream figures speech to be pure nonsense - although it can later often be shown to have a logical meaning.
In addition to the lucidity of the dream-ego, the "lucidity" of the
other dream characters also plays an important role in their communication. In order
to avoid misunderstanding, we can never empirically prove whether or not other dream
characters are lucid, only that they speak and behave as if they were. Elsewhere
I have argued that many dream figures seem to perform with a "consciousness"
of what they are doing (THOLEY, 1985; 1989a). Some of our unpublished work on the
lucidity of other dream figures (in the sense just described) includes examples
which seem to indicate that the dream-ego becomes lucid first. This is followed
by the other dream figures attaining lucidity. On the other hand, we have many examples
of reverse order. We can illustrate this by means of an example in which another
dream character not only becomes lucid before the dream-ego, he also possesses a
higher degree of lucidity than the dream-ego later achieves. This abbreviated form
of the dream was reported by a woman and can be found in REIS (1989b):
I dreamed that I had forced myself through a grey and slimy mass. I didn't know then and I still don't know what it was. It was unpleasant, but for some reason I had to force myself through it in order to advance further. Then, in the midst of this grey slime, I came to a brightly lit place with a person standing in the center. I could see that it was Mr. Spock, the scientist of the Enterprise (the spaceship of the television series Star Trek). He told me, "There is no reason to worry because you are dreaming!" I did not believe him and I asked him what it was that I had just passed through. He answered that I had just passed through my own brain, or my own mind. I did not believe him, but he knew so much more than I did and he told me he would jump up and then remain in mid-air, just so that I would be able to see that we were part of a dream. Only after this actually took place was I convinced that I was in a dream. Then I said that I would never have found out by myself that I was dreaming. He replied that he knew that and that was why he was there. He also said that he knew much more than me anyway and that was the way it should be right then. He explained the meaning of my path in a very plausible manner. . . . He also explained why it was not necessary to know all this right from the start and that he only explained it later on so that I wouldn't be afraid anymore. Anyway, he told me all kinds of things and showed me things that I did not believe right away. I think it was great to have someone acting in a dream who knew much more than I did.
The dream character of Mr. Spock may be characterized as standing for the so-called
internal self-helper (ISH) who gives important advice to the dreamer for her dream
and daily lives. Our previous findings suggest that one can arrange a meeting with
an ISH by means of a suitable pre-sleep suggestion. While lucid dreaming, one can
also arrange meetings with the ISH for a dream in the future.
One often finds an ISH at a place which is difficult to reach and which can be
brightly lit (as in the example with Mr. Spock), or which is situated high up. There
are examples in which one has to climb to the top of a mountain where one meets
an ISH who calls himself a monk, a guru, or possibly a psychotherapist. Others pass
themselves off as guardian angels or helpful ghosts (for an example, see THOLEY
1984). We also have examples of cases where an ISH knows certain things from the
dreamers past - things which the dreamer himself is not aware of even after waking
up, but which further investigation has shown to be true. Suitable phenomenological
experiments are necessary to achieve further clarification concerning this important
component of lucid dreaming.
In view of the fact that literature in the field of lucid dreaming almost exclusively refers to the lucidity of the dream ego, we have, in fact, consciously chosen an example in which the other dream character becomes lucid earlier than the dream-ego and is superior to it. Naturally, there are many other examples in which the reverse is true. In such cases it is helpful if the dream-ego tries to convince the other dream characters that they are in a dream. The quality of the dream can then change completely and communication between the dream characters can take place which may lead to much greater insight than is found in the typical lucid dream. For this reason we consider the "lucidity" of all dream characters (see item II.7 in Table 1) to be a higher form of lucidity. The verbal, or possibly even "telepathic," communica-tion no longer takes place on a symbolic, but rather on a direct level. It has already been possible to confirm this in preliminary phenomenological experiments. I have recently (THOLEY, 1989a) indicated that it was possible to enter the body of another dream character with the ego-core and, in this way, gain more information than was possible with normal verbal communication.
We can draw a whole series of practical conclusions about the ending, prolong-ing
and manipulation of lucid dreams from the results of our phenomenological experiments.
Just as a dream can be ended by fixing a gaze, a lucid dream can be prolonged when
it threatens to end by rapid eye or body movements. As we have already dealt extensively
with the possibilities and limits of manipulating lucid dreams (THOLEY, 1988), we
will only briefly comment.
The control of a dream through the dream-ego's action in the dream world (similar
to the waking-ego's actions in the waking world) is not what we mean by manipulation.
Rather, we mean intervention in the dream world which would more likely be considered
a supernatural occurrence in a waking state; e.g., journeys into the past, transformation
of the dream-ego or dream scenery, etc. Just as lucid dream-ing has been associated
with defense mechanisms, so too has dream manipulation been thought to be a kind
of defense mechanism. Lucidity can, indeed, be used in the sense of a defense mechanism
for escaping problems and conflicts. But, on the other hand, it also offers the
unique opportunity (not possible in normal dreams) to face personal problems and
conflicts, to confront threatening people and situations and even to seek them out,
rather than fleeing from them (see THOLEY, 1988b).
The fact that lucid dreams can usually be ended by fixing one's vision on a stationary
spot makes it possible to closely observe the phenomena which appear during the
transition to a waking state. Given that we have already dealt with such phenomena
in an earlier article (1981), we will limit our remarks here to a few observations
connected with bodily experiences which provide some important background for the
remainder of this article.
Only one body was experienced during the transition from the dreaming to the
waking state. Of special interest to us here was how the transition took place from
an upright, standing dream body to a horizontally lying waking body. This transition
is never experienced as the dream body falling into a horizontal position. Instead,
there is a sudden change of the spatial reference system. This is comparable, while
awake, to when a person wants to go to the door of a completely dark room and suddenly
discovers he is at the opposite side of the room. In this case, it is only the sudden
change of the spatial reference system (constituted by the room) which is experienced,
not the changing of the position of the body through turning and shifting. In further
experiments, we tested to see what happens during the transition from a dream to
a waking state when the dream body is consciously situated in a way not common during
sleeping, e.g., the head and torso bent forward and almost touching the knees, or
the arms and legs extended in a spread eagle fashion. Neither a straightening of
the body in the first case, nor the drawing in of the limbs in the second case,
is actually experienced during waking. Rather, before waking, the body loses its
clear contours and sometimes its solid character. We have applied the metaphorical
term "cloud-like ego" to such an occurrence. Upon fully awakening this
"cloud-like ego" stabilizes into a solid body ego with definitely defined
con-tours and is experienced as lying in bed.
A dream ego and a waking ego have also been experienced simultaneously. For example, the dream body gradually faded out (as in a film), while the waking body became more and more clear. The dream body slipping into the waking body was also experienced, particularly during flying dreams. When a cloud-like ego or a disembodied ego was experienced, it also frequently slipped into the waking body. Occasionally the body was not immediately mobile upon waking, a situation which was very unpleasant for inexperienced lucid dreamers. Practiced dreamers, on the other hand, use this condition to return to a lucid dream state (see THOLEY, 1989c).
Hypnagogic Techniques for Inducing Lucid Dreams and OBEs
The above mentioned hypnopompic experiences were used to develop
hypna-gogic induction techniques which were then employed in an effort to
reverse the above sequence. This sometimes occurs as quickly as with the
reversing of a reversible figure. We have already outlined other hypnagogic
techniques in some of our earlier articles (THOLEY, 1982; 1983a) and later
described them in more detail and illustrated them with suitable examples
(THOLEY, 1989c). In many respects, I personally consider the hypnagogic
induction techniques to be more appropriate for advanced subjects than other
techniques because they allow lucid dreams to be
1. Attained at a particular time;
2. Prolonged easily; and
3. Resumed after short interruptions.
Finally, only hypnagogic techniques made possible a 24-hour period of lucidity
that included the total sleeping state (see item II.8 in Table 1). Indeed, only
a few people have succeeded in accomplishing this in our experiments. I have personally
twice experienced 24 hours of lucidity with approximately a five-hour period spent
in a total sleeping state. EMG measurements showed that my muscular system was completely
relaxed during this time. Upon awakening I showed no signs of either physical or
mental fatigue. A feedback relationship seems to exist between sleeping state lucidity
and waking state lucidity.
So-called OBEs of the most varied sort frequently arise with the application
of hypnagogic techniques. In the following section we will deal with them in more
detail from both the conceptual and phenomenological points of view.
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