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become chaotic, in the strict mathematical sense of the word (Murray (1993)Bib). Roughly speaking this
means that even if we know the precise form of the dynamical equations it soon becomes impossible to
predict with any accuracy the size of a population at a time in the future. And since in practice we are
unlikely to know either the exact form of the equations, or the starting population accurately, the
difficulty of exact prediction becomes that much harder. Consequently the analysis of precise models
may well tell us very little more than our simple model, which by merely noting the sign of the effects of
change actually contains a lot of the useful qualitative dynamics.
These considerations lead to the conclusion that we have found a strong and robust foundation for our
subject in the above simple considerations. They are very general, but very clear. They get to the heart of
the matter. We will be building on this foundation in Part B, to some effect.
Important note on abbreviations.
There may be some readers who are put off by the notation I have introduced. Anything new can be hard
to adapt to. Please note that it is only a form of shorthand. If you think of it as being like the use of
abbreviations, such as NCP&HR for the National Council of Psychotherapists and Hypnotherapy
Register, you may find it easier to understand what it is about.
But shorthand does take a little time to master. I suggest that when at first you see some you avoid the
temptation to let your eye skip over it and simply expand it into the full phrase or sentence it represents
until you become familiar with its meaning. In time you will then be able to work simply with the
shorthand. Compared with the task of a secretary learning Pitman's shorthand the time and effort
involved is very small indeed.
The great strength of a shorthand lies in its simplicity and compactness. We will find this useful when we
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Principles of Hypnosis (3) The importance of the concept of systems in understanding hypnosis
come to analysing different kinds of processes which arise. I re-emphasise that even arithmetic could not
have developed without the use of a good shorthand for the numbers. But of course the use of a
shorthand in itself is not mathematics.
The weakness of a shorthand is that it has to be accurate. A one letter mistake in the degree MA can
make a Master of Arts into a Doctor of Medicine - MD - something that cannot be achieved by a one
letter change to the full phrase.
Finally, for the sake of exactitude, I will make explicit a convention that if a word or phrase is in { } it
refers to the activity of a system, while if it is in ( ) it refers to some quantity that is not. Thus it can be
useful to write /(temperature) > /{sweating}, which would be shorthand for "An increase in the
temperature of a person leads to an increase in the activity of the perspiration system". The subtly
different expression /{temperature} > /(sweating) would mean "An increase in the activity of the sensory
system which registers temperature leads to an increase in the measurable sweat produced". This
distinction is not of great importance at the level of this book, but could be important as the methods
become increasingly precise. For it is NOT always the case that the perceived temperature is the same as
the actual temperature and it may not be the case that a given level of activation of the perspiration
system always leads to the same level of perspiration.
SUMMARY
The notion of a system has been elaborated mainly through examples.
The notion of the activity of an organic system has been introduced, together with a notation which
expresses in a compact form the essential facts regarding the way changes in the activity of one system
may affect the activity of another.
It is important to note the general principle of organic systems that reversing the cause does not
necessarily reverse the effect.
It has been emphasised that Hypnotic techniques have the effect of altering the level of activity of a very [ Pobierz całość w formacie PDF ]