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DR. KLAAS ALTENA TRANCE AND HYPNOSIS DEFINED WITH MODERN LOGIC: APPLICATIONS TO HYPNOTHERAPY
european journal of clinical hypnosis - volume five – issue three – pp. 43-54
TRANCE AND HYPNOSIS DEFINED
WITH MODERN LOGIC:
APPLICATIONS TO HYPNOTHERAPY
▼
Author:
Klaas Altena
Kampen, the Netherlands
Modern logic can help to define trance and hypnosis. Logic constructs different formal languages. Trance
is defined as the mental state in which thoughts are modelled according to one of these formal languages.
Hypnosis is defined as the application of techniques that change the accessibility to these languages for a
person. The treatment of two cases of Obsessive-Compulsive Disorder, two cases of Delusional Disorder,
and an analysis of some aspects of a mainstream approach to hypnosis demonstrate the applicability of
this theoretical approach.
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In modern logic different types of formal languages are
constructed. These languages differ in their power to
approach the complexities of the natural languages. In this
study, it is hypothesized that one of the simplest formal
languages, the so-called language of first-order logic, is a
good approach to the language used by a person who is in
trance. Trance is defined as the state of mind in which
essentially only the language of first-order logic is available
for mental and communicative operations. If trance is
defined in this way then mental problems and paradoxes that
depend upon another type of language cannot exist in a state
of trance. Two paradoxes with serious cognitive and
behavioral consequences, the Liar and the Truth-teller, are
presented in this study as examples of this language
dependency.
The concept accessibility to languages is used to define
hypnosis. Hypnosis is defined as the application of a
technique that changes the accessibility to types of
languages. The hypnotherapist has access to different
languages and changes the accessibility to languages for the
client.
The treatment of some cases of Obsessive-Compulsive
Disorder and Delusional Disorder is taken as an illustration
of this approach. To conclude this study an analysis is made
of some hypnotic language patterns used by Bandler and
Grinder (Bandler & Grinder, 1975; Grinder & Bandler,
1981)
DEFINITIONS OF TRANCE AND HYPNOSIS
The term mental disorder implies that there is a state of
mind that can be called mental order. Let mental order be
described as the condition in which a valid argument is
available for answering questions like: Is it right to think or
to act so and so? The term ‘argument’ refers here to the
process of reasoning in which a conclusion is drawn. In this
study reasoning is used synonymously with argument.
Mental disorder implies a condition in which a valid
argument is not available. Only where Mental Disorder is
capitalized reference is made to diagnoses mentioned in the
Diagnostic and Statistical Manual of Mental Disorders
(American Psychiatric Association, 1994).
Formal Languages
Modern logic tries to answer the question when an argument
is valid. If initial expressions in a formal language of logic
are used to derive other expressions, then these initial
expressions are called axioms or theorems. If an axiom in
such a system cannot be valuated as true or false, this will
cause a condition in which valid reasoning is not available if
reasoning depends on that very axiom. If valid reasoning is
not available to decide if some proposition is true or false,
and if as a consequence a vital question cannot be decided
upon, then thinking may become obsessive. I.e., the
reasoning from premises to conclusion is started again and
again but with no success. If reasoning contains a premise
that cannot be logically valuated as false without producing
a contradiction then no argument of another person can
demonstrate the falsity of such a belief.
The cognitive, emotional, and behavioral consequences of
these disordered mental states can be great. In both cases
the level of complexity of the languages the mind uses is
important. Formal languages differ in complexity. Some
formal languages are so simple that they do not even have
the capacity to simulate certain mental disorders. At first
sight this would be a reason to reject that language as
useless. But this can be reversed. What happens with a
mental disorder if the person involved changes the
language of the mind to a type of language that cannot even
produce this disorder? This approach to a certain domain of
mental disorders makes use of formal aspects of languages.
Maybe those formal aspects are decisive to solve some
mental disorders.
The language of first-order logic
In order to demonstrate the capacity to analyze sentences
from natural language with a formal language some
detailed examples of formal expressions are presented. The
formal language discussed in this section is called the
language of first-order predicate logic, or the language of
first-order logic, or just a first-order language. Form is
essential for the construction of expressions in a formal
language. And form is essential to differentiate between
different formal languages.
Reasoning cannot be conducted with sentences that are not
well formed. E.g., the sentence: All mouthbrooders carry
around in the does not conform to the rules for constructing
a well-formed sentence. Because reasoning is conducted
with sentences that are well formed, the question must be
asked: What is the structure of a sentence? A sentence is
formed if something is predicated of an entity, e.g., The sky
is red. The entity ‘sky’ has the property Red. (In what
follows names for entities are italicized. Names for
predicates are italicized and capitalised.) This sentence is
rewritten, following certain conventions in logic (Barwise
& Etchemendy, 1992), as (Red(sky)): The sky is red. To
avoid ambiguity in the case of composite expressions an
expression is placed between a left and a right parenthesis.
The
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european journal of clinical hypnosis - volume five – issue three – pp. 43-54
expression (Red(sky)) is a claim about the world. In a more
symbolic language the sentence (Red(sky)) can be presented
as (R(s)): R for the predicate Red and s for the entity sky.
Sentences can be more complex, e.g., Dawn loves reality.
The predicate is Loves and there are two entities to be
compared. One entity is dawn and the other entity is reality.
This sentence is represented in the form (Loves(dawn,
reality)): (L(d,r)). The relation Loves is a two-place predicate
because two entities are related. If three entities are related,
the predicate is a three-place predicate. Dawn is a choice
between night and light is represented as (Choice(dawn,
night, light)): (C(d,n,l)).
The following three sentences result:

(R(s))

(L(d,r))

(C(d,n,l))
The capital letters R, L, and C refer to predicates. The small
letters s, d, r, n, and l, refer to individual constants, entities
in the world: persons, things, experiences, imaginations, etc.
If the individual constants are replaced by variables, e.g.,
(R(x)), this formula symbolizes that x is red whatever x may
be. This is a formula but not a sentence in logic, because this
expression cannot be true or false. (In what follows the term
expression is used for both sentences and formulas.) If the
variable is replaced by an individual constant, e.g., sky, or
light, or dawn, the resulting expression is a sentence because
that expression can be true or false. The formula (R(x)) can
also be transformed to a sentence if quantifiers are used.
There are two quantifiers. The existential quantifier is
symbolized as x and means: There exists an entity x such
that…. The universal quantifier is symbolized as x and
means: For every entity x it is the case that…. If an
existential quantifier is placed before the expression (R(x)),
the formula (xR(x)) results, "There exists an entity x such
that x is red". This expression can be true or false. Another
sentence results if the universal quantifier is added. This
results in the formula (x Red(x)), which means that every x
is red. Sentences can be negated by the expression it is not
the case that… symbolized as . The result is a new
sentence, e.g., (xR(x)).
The expressions that can be generated in this way can be
chained together with the help of the conjunct and
symbolized as , the disjunct or symbolized as , and the
implication if…then, symbolized as .
A possible composition of the three sentences above is:
(((R(s))  (L(d,r)))  (C(d,n,l)))
If the sky is red and dawn loves reality, then dawn is a
choice between night and light. This composite sentence
can be true or false. This composite expression belongs to
the language of first-order logic.
Grinder and Bandler (1981) provide an example of joining
sentences together with the help of the conjunct and.
… And as you look about … you can enjoy … the clarity
of the air … the distinctive lighting across the sky …
and you glance down and see… the surface of the beach
… and as you stand there … looking down at the beach
you’re standing on … you can see your feet (…). (p. 45)
This long sentence can be transformed to a composite
sentence using the conjunct  several times. In some
positions of this sentence the conjunct  is implicitly
present.
The type of sentences belonging to the language of firstorder logic does not suffice to analyze all thoughts and
utterances in natural languages. The following sentence
cannot be analyzed with the language of first-order logic.
And as you look about… you are aware of the redness of
the sky… the lucidity of your awareness… the transparency
of your thinking about the lucidity of your awareness. Here
the property transparency is a property of thinking about
lucidity, and the lucidity is a property of awareness. In the
formulas of first-order logic there is no place for such
constructions.
There is a lot more to say about the construction of wellformed sentences, but this will suffice for the purpose of
this study. For introductions on modern logic, see Barwise
and Etchemendy (1992), Gamut (1991a, 1991b) and
Stolyar (1970).
Other formal languages
If a formal language is constructed in which the object of a
predicate is itself a predicate, the language is no longer a
first-order language but a second-order language. The
sentence: It is unethical to be egoistic is a sentence in
which the property of being egoistic (E) is assigned the
property unethical (U). In formal symbols: (U(E)). If the
phrase is false is understood as a predicate on the same
footing as Blue at least a second-order language is needed
to construct the sentence: Everything they think of me is
false. The phrase everything they think of me refers to a set
of properties assigned to the entity me. And whatever
property is assigned to the entity me, this property has the
property of being false. However, the use of is true or is
false as predicates in a sentence creates paradoxes. This use
of is true and is false in
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sentences belonging to a language of higher-order logic, may
result in obsessive or irrational thinking.
First-order predicate logic constructs expressions as
mentioned before. Second-order logic constructs expressions
that assign a property to a property or to a set of properties.
Third-order languages predicate something of sentences
containing predicates that predicate something of a predicate
or of set of predicates. Second-order logic therefore has the
capacity to analyze sentences that are of a more complex
nature than the sentences that first-order logic can analyze.
There are other kinds of logic. Modal logic deals with
expressions that contain the element it is necessarily so that
and it is possible that. Tense logic deals with expressions
that contain the elements it is always going to be the case
that, it always has been the case that, it will at some stage in
the future be the case that, it was at some stage in the past
the case that.
Suppose a client tells the hypnotherapist, “I have no other
choice than to hit my son”. The first impression is that this is
a sentence that cannot be analyzed with the first-order
language. The language of modal logic can analyze it as the
following sentence: It is necessary so that I hit my son. The
second impression is that the client is probable not in trance.
In a state of trance one does not expect such sentences of the
person. The same applies to the sentence: I have always been
an honest person. Tense logic can analyze this sentence. If
the person who expresses this sentence is expected to be in
trance then the hypnotherapist is justified to doubt that this
person is really in trance. Again, such impressions tell
something about the intimate connection between language
en trance. If a person is expected to be in trance, he is not
able to think or utter sentences that belong to higher-order
logic, modal logic or tense logic and other forms of logic. He
will not be able to tell the hypnotherapist: You have possibly
at some stage in the induction interspersed some suggestions
in your sentences. This means that in a state of trance certain
languages are not accessible.
PARADOXES THAT CAUSE OBSESSIVE AND
IRRATIONAL THINKING
predicate is false. One of the sentences this sentence refers
to is the English sentence: All sentences formulated in the
English language are false. Therefore this sentence refers to
itself. If a sentence is produced in the English language,
then the question if this sentence is true, cannot be solved.
If this sentence is valuated as true, it must be admitted that
therefore this sentence is false. But if this sentence is
valuated as false, one must admit that therefore this
sentence is true. This kind of self-reflexive sentences
therefore causes what usually is called the Liar paradox
(e.g., Barwise & Etchemendy, 1987). The structure of a
sentence of this type can be represented by the expression:
This sentence is false.
A proposition is that what is expressed in a sentence:
uttered, written down or symbolized in some other form.
The set of propositions in an axiomatic system that refer to
themselves and cause this kind of logical trouble, is called
here the set A. Propositions belonging to this set are called
in the present study A-propositions. If an A-proposition
functions as a premise in an argument, or the truth of at
least one of the premises depends on this A-proposition,
then the argument cannot be concluded. Especially in the
case of vital or moral questions of the general form: Is it
right to think or to act so and so? This may result in
obsessive thinking. If it is possible that such an Aproposition changes into a proposition that is either true or
false but not both, then that problem is solved. The
existence of Liar-like paradoxes is a symptom of
something, namely that a person can reflect upon his own
language constructions or upon his own thinking. This view
suggests that the need to reflect upon one’s owns thoughts
and to negate the content of these thoughts at the same
time, is at the source of the problem.
Suppose the following argument in which P and Q are
propositions that can be expressed as a sentence:

Premise 1: If (it is the case that) P then (it is the
case that) Q

Premise 2: (it is the case that) P

Conclusion: Therefore (it is the case that) Q
An example is:
The Liar

A sentence is formed if something is predicated of an entity.
But what happens if something is predicated of a property or
of a sentence or predicated of a class of properties or a class
of sentences? E.g., when the sentence is formed: All
sentences formulated in the English language are false. This
sentence refers to a set of sentences and contains the
If I am responsible for my children (P) then I have
the responsibility to check whether their drinks are
safe (Q).

I am responsible for my children (P),

Therefore I have the responsibility to check
whether their drinks are safe (Q).
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This reasoning from two premises to a conclusion is
straightforward. But suppose now that the truth of
proposition P depends upon an A-proposition. An example
of an A-proposition that might function as an axiom or
theorem for the argument presented above is expressed in
the following sentence: I am not responsible for my thoughts
about responsibility. In that case it is not possible to
construct an argument in the form cited. The argument
cannot be concluded how often you try to reach a
conclusion.
The proposition I am responsible for my children is a
thought about responsibility. On the ground of the Aproposition, I am not responsible for this thought. But if I am
not responsible for a certain thought then I am not
responsible for the conclusion of an argument that contains
this thought. Even this last thought is a thought about
responsibility and falls under the scope of the same Aproposition. If the matter at hand is of any urgent or vital
interest, then thinking from premises to conclusion is a
necessary step but cannot be concluded and has to start again
and again. And that is a characteristic of much obsessive
thinking. Confusion likewise results if the A-proposition is
all my thoughts about responsibility are false. In that case it
seems not even possible to think the first and second
premise, because it is not possible to valuate them as true.
The argument given above is but one type of argument that
causes logical confusion if it falls under the scope of an Aproposition.
The Truth-teller
Another kind of paradox results from the Truth-teller. The
Truth-teller is expressed by the sentence This sentence is
true. This sentence, like the Liar, refers to itself. At first
sight this sentence does not seem problematic. But if the
question is asked if the sentence as a whole, namely This
sentence is true, can be possibly false, logical problems
arise.
The argument runs as follows. A sentence is an expression
that can be true or false. Consider the following possibilities:

This sentence is true, is true

This sentence is true, is false
First consider possibility (1) that the expression is true is
considered to be a logical valuation as it appears as part of
the italicized sentence. In that case things seem to be
consistent. But if in (2) the first appearance of is true is a
logical valuation, it contradicts the valuation is false outside
the italicized sentence. If in some reasoning, This sentence is
true functions as a premise and is valuated false, then this
reasoning cannot proceed because of this contradiction.
Therefore, a Truth-teller belongs to the type of Apropositions.
In the case of the Truth-teller a sentence can be constructed
such as All my thoughts about responsibility are true. This
sentence as a whole contains its own truth predicate and a
contradiction results if one tries to valuate this whole
sentence as false. Suppose the following argument in which
P and Q are propositions:

Premise 1: Either P or Q

Premise 2: not-P

Conclusion: Therefore Q
Now suppose that P is a Truth-teller, then premise 2 is a
contradiction and the conclusion therefore Q is not
possible. The conclusion is not simply false. The
proposition P cannot be false and this proposition forms a
possible source of irrational ideas that cannot be corrected.
A mental disordering may result.
The language of the Liar and the Truth-teller
In the foregoing an A-proposition is described as a type of
proposition that may contain its own truth predicate as in
the following sentences: This sentence is false, and, This
sentence is true. But this rests on the assumption that is
true and is false are properties on the same footing as the
properties Red, or Loves, Between, Egoistic, and Unethical.
If simple sentences are composed like, This ball is blue,
and, This ball is true, the difference between is blue and is
true is evident. A ball may be blue but a ball cannot be
valuated as true. Nor can a ball be valuated as false. For a
discussion of this and related topics see Soames (1999).
In first-order logic a sentence is composed of a predicate
and an object. In first-order logic the expressions is true
and is false cannot be used as predicates on the same
footing with other predicates. Suppose it is made
impossible to use a language in which the expressions is
true and is false function as predicates. Or suppose it is
made impossible to use a language that does allow the
construction of a sentence that refers to itself. In those
cases an A-proposition cannot be presented as a wellformed formula. And that eliminates the problems with
these A-propositions. But how can the person involved
reconsider the syntactic and logical function of the terms is
true and is false? This question is especially difficult to
answer when the use of the predicate is deeply buried in the
process of thinking and reasoning. And it is too difficult an
enterprise to teach the client to change the position of the
valuations is true and is false.
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There are several extensions of first-order logic. These
extensions generate more complex sentences than can be
constructed in the language of first-order logic and are
therefore more suitable to describe the sentences of natural
languages. But the Liar paradox and the Truth-teller
described above, need just such an extension of the language
of first-order logic. If this is true, then a restriction of mental
activity to the language of first-order logic does not permit
the construction of paradoxes like the Liar paradox and the
Truth-teller. And this is the place where trance and hypnosis
enter the story.
THE DEFINITION OF TRANCE
A state of trance induced in hypnosis seems a rather strange
and inexplicable state. But this depends on the perspective
one chooses. The instructions given by the hypnotherapist to
the client form a key to understand what happens in trance.
The instructions often imply that the client must concentrate
on sensory-grounded experiences or sensory-grounded
fantasies. A state of mind is then created in which the client
forms and uses sentences that are of the type constructed in
the language of first-order logic.
Therefore: Trance is defined as the state of mind in which
only sentences are used which belong to the language of
first-order logic.
This definition implies that in trance only sentences can be
formed which connect a predicate with an individual object.
The object of a predicate cannot be a property, a set of
properties, a sentence or a set of sentences. And a sentence
constructed in a state of trance cannot contain its own truthpredicate. This excludes in a state of trance the formation
and use of propositions that are expressed by sentences like:
1. The light feeling in my left arm is a pleasant feeling.
2. My right arm lifts as an utterance of my will.
3. This particular sentence I think is not of my own
making.
4. All what you (the therapist) tell me is sensorygrounded.
5. You (the therapist) apply the technique of pacing
and leading.
The state of trance includes the possibility of sentences like:
1. My left arm feels relaxed.
2. It is not the case that my right arm is relaxed
3. My right arm is lifting.
4. I imagine a cloud drifting through the sky.
5. I see a rabbit
This means that in a state of trance, the client is not able to
judge if his reactions, e.g., sensorimotor responses, happen
out of free will or not! If this judgement should be made,
some sentence such as, My right arm lifts, as an utterance
of my will, must be constructed. But this sentence contains
the expression Lifts as a predicate and this predicate is the
object of the predicate Is an utterance of my free will. Such
a sentence belongs to the language of higher-order logic. In
a state of trance therefore the client cannot make a
judgement about what the therapist wants or what the client
wants. This is characteristic for a trance situation. Any
observator can tell that a client lifts his arm because the
hypnotherapist wants that to happen. But the client
experiences an estrangement and cannot tell you if he does
comply with the therapist or not.
The same reasoning applies to the instructions the therapist
utters. The method to induce a state of trance is to instruct
the client to concentrate exclusively on individual objects,
e.g., a spatial object, a finger, or an image, or other sensory
impressions. This concentration results in a sensorygrounded experience. The instruction, You feel the warmth
in your right hand, helps to induce trance. But not the
instruction, Judge if the warmth in your right hand feels
good or bad. The instruction, Concentrate on the force that
lifts your left arm, furthers the state of trance. But the
instruction, See if your left arm lifts fast enough, does not
further the state of trance.
It is important to note that the truth-value of the sentences
used by the therapist or client does not really matter. Even
if sentences uttered by the therapist are logically false
assertions or false predictions, if they induce a tendency to
direct attention to sensory-grounded experiences they
enhance the probability that the client uses a language of
first-order type. This explains why the therapist can make
use of a predictive sentence like: Your arm slowly stiffens.
It is not necessarily the case that the arm is stiffening
slowly. The effect of the prediction is in any case that the
attention of the client is directed on sensory experiences in
the arm.
Relaxation techniques often induce a trance. The person
who instructs relaxation directs the focus of attention to the
experience of one’s bodily state. For a discussion of the
concepts, theories and techniques with respect to
relaxation, see Poppen (1998). To direct attention to a
physical state is to induce in the person the tendency to
construct formulas in the language of first-order logic. If
the relaxation technique is instructed according to the rules,
the language of first-order logic can represent the language
used, whether or not relaxation is
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effectively reached. It should be noted in passing that in
therapeutic approaches that rely on conversations and
analysis of the cognitive activities, e.g., irrational thoughts,
of the client, a language is required that must be represented
by a formal language that is more complex than the language
of first-order logic.
thinking. But a better explanation is that the person who is
in trance has not access to language constructions that may
describe these inconsistent perceptions. The person in
trance has not even access to constructions that use the
expression inconsistent perceptions because then at least a
higher-order language must be used. But such a
construction would contradict the state of trance.
THE DEFINITION OF HYPNOSIS
The hypnotic distortion of time is another phenomenon that
can be explained using the meaning of trance as defined in
this study. It is commonly reported that in the absence of
specific suggestions of time speeding up or slowing,
subjects underestimate time spend in a trance. But
generally time estimates are poor. In a state of trance time
estimates bring the person out of trance because time
estimates require a language with tense constructions.
Therefore, if time estimates are asked for an episode in
which no tense constructions could be used, these estimates
will be inaccurate.
Language L1 is accessible from language L2 if sentences
belonging to language L1 can be reflected upon in sentences
belonging to language L2. Language L1 is inaccessible from
language L2 if in sentences belonging to language L2 no
reflection is possible upon sentences belonging to language
L1.
If a hypnotherapist uses hypnotic language patterns the
hypnotherapist prevents the hypnotized person to reflect
upon those very hypnotic language patterns. If the state of
trance can be defined as a state in which the person has only
available a first-order language, then other levels of
language are not accessible from this state. Sentences,
thoughts or utterances that require for their analysis a
second-order language or other complex formal language are
not accessible from a state of trance. It is therefore not
possible in a state of trance, to formulate complex sentences
such as, The relaxed feelings I experience are temporary
feelings. In that particular sentence a property of feelings,
namely being relaxed, is attributed the second-order property
of being temporarily.
Language constructions that involve modal or tense
constructions are likewise not accessible from a state of
mind that only uses a first-order language. It is possible that
the hypnotherapist uses a tense construction to produce a
posthypnotic effect. But the production of a posthypnotic
effect rests upon the assumption that the person in trance
does not reflect upon sentences with a tense construction. So
in order to produce a posthypnotic effect, the hypnotherapist
uses another language than the person in trance. The
language of the person in trance is accessible from the
language of the hypnotherapist but not vice versa. This nonaccessibility of certain levels of language from a state of
trance explains some trance phenomena.
In Udolf (1987, chap. 4) some trance phenomena are
described and two of them are explained below. Trance logic
refers to the ability of a hypnotized subject to tolerate,
without apparent disturbance, the coexistence of two or more
logically inconsistent perceptions or ideas. An example is
the perception of a hallucinated person in one location and
the real person in its actual location simultaneously. This
phenomenon is explained as the suspension of critical
The definition of hypnosis in this study does not refer to the
state of mind the client is in but to the activity of the
hypnotherapist:
Hypnosis is the technique to change the accessibility of
languages.
The hypnotherapist is thus considered capable to use
language in order to restrict or to enlarge the set of
languages for thinking, reasoning and communication of a
client.
This definition has consequences for the interpretation of
ideomotor responses. Not the content or meaning of a
response is important, but the form. Imagine a possible
hypnotic technique the application of which results in the
raising of the right and left arm. The therapist usually
induces the raising of the arms by instructions in the
language of first-order logic, e.g. Your arm feels light, In
your arm you feel a lifting power, Your arm lifts. This
happens under the condition of high concentration on
sensory-grounded experiences. If movements of arms or
fingers are used as utterances of the valuations is true and
is false the term ideomotor response is used.
Often it is agreed between therapist and client that
following a sentence uttered by the therapist, a client's
movement of the right hand means is true or yes and that a
movement of the left hand means is false or no. But it is of
no importance which valuation is associated with the
movement of the right and left hand. It is of importance
that the client learns a two-valued response. The client
either valuates the sentence of the therapist as true or as
false, but not
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both true and false at the same time. The client should not be
tempted to rethink the utterances of the therapist and reflect
upon these utterances. This would reintroduce for the client
the necessity of constructing sentences that belong to more
complex languages. This would end, by definition, the state
of trance.
APPLICATIONS
the client in trance concerned her ways of finding true
answers for the problems that bothered her. A great deal of
the sessions was devoted to create a lifting of the arms such
that the client experienced an estrangement with respect to
the lifting of her arms and the is true-is false answers.
There were 12 sessions and the positive effects of the
procedure became manifest in de months following. The
symptoms disappeared.
Case 2
The Liar and the Truth-teller
In this section a hypnotic procedure is described that was
successful in the treatment of two clients suffering from an
Obsessive Compulsive Disorder. Another hypnotic
procedure is described that was successful in the treatment
of two clients suffering from a Delusional Disorder. It is
assumed that the two Obsessive Compulsive Disorders
resulted from a Liar type paradox. Furthermore it is assumed
that the two Delusional Disorders resulted from the Truthteller paradox. The application of the procedure followed in
case 1, describing the treatment of a client suffering from an
Obsessive Compulsive Disorder, was so surprisingly
effective that this required an explanation. This explanation
is developed during applications and modifications of the
technique. The successes and failures lead to the theory
presented in this study.
The Liar: cases
Case 1
In case number 1 the person repeatedly doubted if she had
performed an act such as having accidentally contaminated
the food and drinks of her children. The care for her children
caused problems because she constantly doubted if she had
not endangered them. This symptom was part of the more
general fear to have any noxious effect on the health and
well-being of others. But she had also great doubts if she did
the things she thought she did and if she had made the
statements that she thought she made to others. She feared
having said the wrong things to other persons. But she could
not remember what she had said. And she suffered great
uncertainty because she thought she acted not responsible.
And she was constantly in doubt about the truth of what she
had said.
It was supposed that an A-proposition like All my thoughts
about my responsibility are false, caused her problems. A
trance was induced and a procedure was followed in which
both arms levitated. A movement of the right hand in
response to an utterance of the therapist was regarded as a
sign for is true. An involuntary movement of the left hand
was regarded as a sign for is false. The questions asked to
In case number 2, the client also repeatedly doubted
whether she had performed an act such as having
accidentally contaminated the food and drinks of her
children. The other symptoms were present too. This time
the client was brought in trance and under this condition
questions were formulated in terms of first-order language.
These questions were chosen directly from the pool of
questions that bothered her. A few applications of this
procedure reduced her problems to a subjective level of 4060% within a few weeks. No further progress was made in
the weeks following. A few months later the diagnosis of
her problem was approached from another angle. When
asked if she felt unique, she admitted with a blush and full
of shame that she considered herself a unique person. She
also thought that other persons knowing her were probably
so jealous of her that they would find pleasure to humiliate
her. When the procedure was applied again, formulating
first-order questions referring to her uniqueness, the effect
was decisive. The symptoms of the Obsessive-Compulsive
Disorder disappeared rapidly to a subjective level of 5%.
The Liar: hypnotic procedure
As a first step the client suffering from an ObsessiveCompulsive Disorder was informed that hypnosis would be
applied and that levitation of both arms would result. Then
the client was informed that a movement of the right or left
hand should be interpreted by the hypnotherapist as a
response to a statement of the hypnotherapist. A movement
of the right hand would be interpreted as the valuation is
true and a movement of the left hand as the valuation is
false. This was the instruction in the first reported case. In
the second reported case the client was told that the
movement of a hand meant is true or is false but not both.
The client was also told that de meaning of a movement
was not fixed but could vary over sentences responded to.
The instructions for the second case were intended to
prevent any tendency of the client to interpret responses to
sentences of the therapist. Such a tendency would bring the
patient out of trance.
A generalisation of the procedure is the following.
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When the client is in trance, the therapist asks questions
related to the obsessions of the client. The sentences that are
uttered by the therapist should be derived from the set of
expressions that describe the problem of the client. They
should be reconstructed as sentences belonging to the
language of first-order logic. After the utterance of such a
sentence the therapist waits until an unambiguous ideomotor
response is true or is false is seen by him and
unambiguously is felt as a movement by the client. The
hypnotherapist then proceeds until all selected sentences are
uttered and responded to. This procedure can be repeated
using the same set of questions or another set of questions,
depending on the definition of what constitutes the Liar
paradox in that particular case. In applying this procedure,
the hypnotherapist should (1) avoid interpreting the answers,
and (2) avoid searching for logical consistency of the
answers.
The Truth-teller: cases
Another hypnotic technique was applied in two cases of a
Delusional Disorder. It was hypothesized that the relevant
delusional or irrational thoughts and reasoning are dependent
on sentences that contain their own truth-predicate is true.
These delusional thoughts therefore belong to the class of
Truth-tellers.
Case 3
In one client the Delusional Disorder was of a Persecutory
Type: the belief that the client was being conspired against,
that he was spied upon by spies from his native country, and
that his brain should be poisoned by spies from that country.
This thought occupied his mind continuously, made it not
possible to make sufficient progress in his work, ruined his
sleep and threatened his marriage. It was supposed that
somewhere in the mind of this client an A-proposition was
operating that made it impossible to valuate a certain
proposition as false. A trance was induced by asking the
client to concentrate unremittingly on the feeling in his back
and his head. It was supposed that this eliminated the
possibility of forming Truth-teller paradoxes. After this first
episode of concentration the client was asked to concentrate
on his back and his head while at the same time thinking the
thought that his mind would be poisoned. This procedure
consisted essentially in two subsequent episodes of two
minutes and was repeated several times in episodes of one
minute. The whole procedure was repeated six times over a
series of 14 sessions, each time with a different aspect
regarding the persecution. At home he exercised frequently.
His unwavering conviction became unstable. He began to
doubt his formerly unwavering convictions about
persecution, and at last decided that his convictions were
only valid in the past.
Case 4
In the other client the Delusional Disorder was of a
Somatic Type. The initial Diagnosis was Vaginismus. After
a series of sessions it became clear that she suffered from a
Delusional Disorder. She was convicted that the right half
of her face was ugly and misshapen. She tasted blood in her
mouth. And she also thought her breasts and vagina were
ugly and misshapen. In this case it was also supposed that
in her thinking a proposition was operating that would
make it impossible to valuate convictions about her selfimage as false. In the first application of the procedure she
was brought in trance by instructing her to concentrate on a
sensory experience. The next episode she was asked to
concentrate on a sensory experience and at the same time
on the thought that parts of her body were ugly misshapen.
In the subsequent session the standard procedure, as
described in the next section, was applied twice. This
standard procedure appeared to work well. After the second
session she reported that her image of mutilated face,
vagina, and breasts was fading away. She presented a rather
large and colorful drawing of herself, the image of herself
how she felt she really was.
Case 5
This client was obsessed by compulsive imaginations about
bad behaviors, e.g., causing a deadly fall of his grandchild
from the stairs or steering his car to the wrong side of the
road in order to cause a fatal collision. Treatment of this
client as if the problem was caused by a Liar-type Aproposition had no success. Both hands responded with
large amplitude in answer to each question. This did not
satisfy the criterion of an unequivocal is true-is false
response. Application of the Truth-teller procedure during
one session and exercises at home had success. The force
of the obsessions and compulsions reduced to a subjective
level of 20%. This reduction was deemed enough by the
client and therapy was ended.
The Truth-teller: hypnotic procedure
The technique in standard form resembles the technique of
systematic desensitization. In the first episode in this
procedure the client concentrates two minutes incessantly
and unremittingly on the experience of feeling support of
the body given by the chair, e.g., the support felt in the
back. In the second episode the client is instructed to think
two minutes with a high degree of concentration the
relevant irrational thought while at the same time
unremittingly concentrating on the feeling of physical
support. The hypnotherapist indicates when it is time to
change.
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The procedure is repeated with episodes of one minute: first
one minute concentration on the support felt in the back,
then one minute concentration on the support felt in the back
and concentration on the relevant thought. The total time of
this exercise is 11 minutes.
After repeating the whole procedure a number of times it can
be expected that the emotive content and behavioral impact
of the irrational thought decreases. The explanation is that
the high level of concentration on a real physical experience
restricts the language of the mind to the level of first-order
logic and therefore excludes the possibility to construct
sentences that contain the predicate is true. Therefore this
technique changes sentences of the Truth-teller type into
first-order sentences. The amount of exercise determines the
growth of the ability to access different levels of language.
A variant of this procedure replaces the concentration on a
thought by concentration on the image that this thought calls
up. This image is then projected on an imaginary plane at a
distance of a few meters from the client. During the
application of this procedure the images may change
spontaneously. This change in images expresses a change in
underlying propositions that belong to the language of firstorder logic. Therefore this change should not be interpreted
by the hypnotherapist or by the client, because this would
mold the propositions into another type of language. This
possibly annuls the positive effects of this procedure.
Application of this procedure in case of anxiety provoking
thoughts appeared to be effective for many clients.
DIFFERENCE IN TREATMENT PROCEDURE FOR
THE LIAR AND THE TRUTH-TELLER
There is a difference between the procedure applied to the
Liar and the procedure applied to the Truth-teller. This
difference is with respect to the valuation. In case of the Liar
an explicit is true-is false valuation by the client of sentences
uttered by the hypnotherapist is build in. In case of the
Truth-teller only a thought must be thought by the client, no
explicit valuation is required and the hypnotherapist presents
no sentences. This difference in procedure has to do with the
valuation problem the clients have. In case of the Liar, a
sentence is false when true and true when false. The
consequence is that valuations jump rapidly from is true to is
false to is true and so on. This jumping must be explicitly
counteracted in the treatment.
In case of the Truth-teller there is no such jumping between
truth-values. The Truth-teller valuates itself as true and this
continues all the time. Premises or arguments that are not in
line with this Truth-teller lead to contradiction and therefore
must be rejected as happens when in scientific reasoning
the reductio ad absurdum is applied. This is reflected in the
procedure. The same thought is presented to the person
without interruption during a certain episode. The transition
to episodes in which no thought was presented was deemed
necessary to keep the person in trance.
INTERPRETATION OF THE NLP APPROACH TO
TRANCE AND HYPNOSIS
The theory expounded in this study can be labeled as a
linguistic approach to hypnosis. The approach of the NLP,
Neuro-Linguistic Programming, is also a linguistic
approach. The following analyses are intended to
demonstrate that some core aspects of the NLP approach
are consistent with the theoretical view of the present
study.
If Grinder and Bandler (1981) induce a state they call
trance then the client’s language for thinking and
expressing thoughts becomes restricted to a first-order
language. Pacing, as described by Grinder and Bandler, is
the technique to make accessible those thoughts that refer
to sensory-grounded experiences. Hypnotic language
patterns uttered by the hypnotherapist amplify these
sensory-grounded experiences. The state of mind that
develops in this way conforms to the definition of trance in
the present study. Leading is the technique to suggest
experiences while the accessibility of other languages that
allow reflection upon these suggestions, is excluded.
Leading therefore is a process that leads a person out of a
language that allows reflection.
If you are in a state in which you are limited, and you try to
make changes in those limitations with your normal state of
consciousness, it’s a “catch-22” situation. Those limitations
will constrain the way you deal with the limitations, and
you are going to have a lot of difficulty. (Grinder and
Bandler, 1981, p. 31) This confirms the hypothesis that the
technique of pacing and leading is in agreement with the
definition of hypnosis in the present study.
Utilization is the technique to utilize resources of the
unconscious. A closer look at the wordings reveals that the
hypnotherapist often uses expressions of the type There
exists some x such that x is y. An example is And you can
allow your unconscious to present you with some memory
from the past that you can enjoy…(Grinder & Bandler,
1981, p. 101). A translation of this expression into the
language of first-order logic is, You will have a memory (x)
such that this memory (x) is enjoyable. The structure of this
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expression belongs to the language of first-order logic. In
this form the expression is a formula but not a sentence. A
sentence is an expression that can be true or false. Because
the expression cited is a formula, the client in trance changes
the formula into a sentence by giving the variable x a value.
This happens because trance is by definition a state of mind
in which sentences are formed and used, not formulas. The
expression uttered by the hypnotherapist becomes true if
there is a memory that satisfies this sentence. The
unconscious therefore can be understood not as an undefined
source of solutions but as the capacity to utilize the formulas
of the hypnotherapist to create true sentences.
Some hypnotic language patterns make use of
presuppositions. There are several techniques available to
the hypnotherapist to state what the hypnotherapist does not
leave open for discussion or opinion. The examples given by
Grinder and Bandler (1981) can be commented upon as
follows.
If the client questions the expressions containing
presuppositions, the client must form sentences that are
reflections upon sentences of the hypnotherapist. But in that
case the client is by definition out of trance. If the client
stays in trance and therefore cannot reflect upon the
expressions of the hypnotherapist, no presupposition is
signalled.
Take the following utterance of a hypnotherapist I don’t
know if your right or your left hand will lift with unconscious
movement (Grinder & Bandler, 1981, p. 245). The structure
of this sentence is (A  B) Sentence A is true or sentence B
is true or both sentences are true. Grinder and Bandler
assume that this presupposes that one of your hands will lift.
This argument is valid only if it is presupposed that the
whole disjunction between parentheses (A  B) is true. (A
and B are called disjuncts, the whole expression (A  B) is
called a disjunction.) But the expression in this case is more
complex. The hypnotherapist utters an expression beginning
with the epistemic phrase, "I don't know". Epistemic phrases
cannot be accounted for in the language of first-order logic.
Given the truth of the whole expression (A  B) without
epistemic phrase, the client has the freedom to make this
expression true by lifting the right hand, the left hand, or
both hands. Assuming that (A  B) as a premise is true, A,
or B, or both A and B will be valuated true. This is perfectly
reasonable.
Therefore one hand or both hands will lift. The reasoning of
the person in trance conforms to logic, assuming that this
person only uses the language of first-order logic. But if the
person involved is not in trance other things may happen.
The epistemic phrase, "I don't know", may then become
part of the argument. And also the person can doubt the
presupposition of the utterance. The same capacity to
reason according to laws of logic therefore will probably
have another outcome if the person is out of trance and uses
another type of language.
The way the hypnotherapist composes elementary
expressions to composite expressions using verbal and nonverbal means is decisive for the expression the person in
trance will notice. Non-verbal signs that separate or unite
utterances to elementary or composite expressions are
therefore extremely important because this information is
decisive for the composition of an expression and therefore
is decisive for the response.
An example (Bandler and Grinder, 1975, p. 24) may clarify
this:
(1)…I knew a man once who really understood how to
feel good about…
(2)…I knew a man once who really understood how to
feel good about…
The phrase in bold feel good receives non-verbal emphasis.
Expression (1) can be analyzed as a composite expression
(1) ((I knew a man once) and (That man really understood
how to feel good about x)) The structure of this expression
is (A1  B1). If this expression as a whole is accepted as
true, then logic prescribes that the two constituent
expressions A and B both must be true.
Expression (2) is also a composite one, but if the fragment
Feel good receives an intonation that contrasts with the
context then the composite expression might be (2) ((I
knew a man once who really understood how to y) and
(Feel good about x))
Expression (1) and (2) are quite different. If the person in
trance gives the variables y and x values, then (1) and (2)
will have different results. This analysis emphasizes the
importance of the non-verbal dimension. If this dimension
is accounted for, the reasoning of the person in trance may
seem more logical.
Discussion
The results of this study allow the following conclusions:
1. The definitions of trance and hypnosis can be stated in
terms of formal languages. A detailed comparison with
other theoretical orientations falls outside the scope of this
study. But the following
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remarks can be made. Sometimes it is suggested that in
hypnotic states of consciousness reasoning is illogical. But
this point of view is disputable as is argued in this study. The
argument is as follows. Reasoning depends on premises.
Some premises that are well-defined expressions in one
formal language cannot even be formulated in another
formal language. The laws of logic however do not differ.
Therefore, reasoning of a person in trance may seem to be
illogical from the point of view of the hypnotherapist who
uses perhaps premises that cannot even be formulated by the
person in trance.
Some definitions refer to language and communication. A
recent example is the book Hypnotic language: Its structure
and use, in which book Burton and Bodenhamer (2000)
state, "All communication invites the receiver into a
hypnotic trance.” In this text, a hypnotic state or trance
refers to a focussing of attention on a thought, idea, concept,
thing, etc. which excludes all other focussing on anything
else" (p. 4). The definition of Burton and Bodenhamer
agrees with the definition of trance in the present study only
if the person focuses on sensory-grounded experiences. If a
person focuses upon thoughts, ideas, or concepts, according
to Burton and Bodenhammer a hypnotic trance is also
created. In the definition of the present study this state of
mind is by definition not a state of trance.
REFERENCES
2. This study shows that some forms of obsessive and
irrational thinking can be analyzed in terms of formal
languages and treated with hypnotherapeutic methods. Is the
language dependency restricted to the few cases discussed in
this study or applicable to the type of Disorders discussed?
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Part of the manuscript was presented at the 9th Congress of the European Society of Hypnosis in Psychotherapy and
Psychosomatic Medicine, Rome, Italy, September 25-29, 2002: Hypnosis and the Other Therapeutic Modalities in the New
Millennium. The abstract of this presentation is titled: Formal logic, Mental Disorder and Hypnosis.
The author is greatly indebted to Henk Broer, Prof. of Mathematics, and Eric Vermetten, MD, for their comments on drafts
of the manuscript.
Address correspondence to Klaas Altena, Zegge 35, 8265 CM Kampen, the Netherlands. Or e-mail, klaasaltena@planet.nl