Paper: “Fuzzy Logic and Nursing” by Eun Ok Im and Wonshik Chee
Summary by Ayanna Miller
Introduction
This paper presents and suggests fuzzy logic as a way to overcome the conflicts
between objective and subjective areas, with respect to gray areas between black and
white answers for questions and gives a contextual understanding of difficult nursing
issues. It gives a brief description and history of fuzzy logic and how it has advanced and
how it is being used in the academic world. The paper defines fuzzy logic and gives
examples of fuzzy sets and membership functions which are the necessary basics of fuzzy
logic.
It includes a discussion on the way fuzzy logic agrees with three categories of
epistemological views of nursing such as correspondence, coherence and pragmatism.
Then it concludes with fuzzy logic in reference to four philosophical thoughts in nursing
they are post empiricism, pragmatism, feminism and postmodernism.
History of Fuzzy Logic
The notion of fuzzy logic has been around for several years with different names and
in the ideas of several philosophers.
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Bertrand Russell a logician position was that if we don’t have enough information
about our environment we are blind to the world. He laid the logical foundations
for fuzzy logic but never bothered to pursue it any further.
Werner Heisenberg a physicist that discovered the uncertainty principle of
quantum physics. He showed that we have limitations in our ability to get
knowledge and that one cannot determine the position and speed of subatomic
particles.
Lotfi Zadeh redeveloped fuzzy logic and published a paper called ‘Fuzzy sets’
and applied Lukasiewicz’s multivalued logic to sets of groups of objects and
called it fuzzy because it had pieces with different degrees.
Fuzzy Logic is known as a logical system and is almost identical with the theory of
fuzzy sets. It is also viewed as a methodology for computing with words rather than with
numbers.
What is Fuzzy Logic?
In this paper fuzzy logic is the use of fuzzy sets in the representation of vague
information about nursing issues. Foundations of fuzzy logic include fuzzy sets,
membership functions, logical operations and if then rules. A fuzzy set is a mathematical
set without a clear defined boundary. Most natural languages used to express knowledge
and information has a lot of complexity, imprecision and vagueness. These same words
can be used to describe nursing. There is a general sense of fuzziness about certain
issues.
Some examples include a description of healthy, a depressed patient, the
classification of some objects as large and also the classification of people by age such as
old or young. These examples are complex and fuzzy in the sense that they cannot be
sharply defined. Other examples in nursing such as words to describe pain can be
complex and fuzzy. Using fuzzy sets we can draw membership functions of strong sharp
pain, moderate pain and mild sharp pain. A membership function represents a degree of
membership to the set. Depending on the information gathered from different patients
the membership function can be represented with different mathematical functions which
allows mathematical operations to incorporate different issues in nursing.
Epistemological views of nursing
Meleis divided nursing into three categories:
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Correspondence – this view requires sensory data, variables and operational
definitions. It focuses on a set of rules and norms. It tends to stress verification
and falsification and makes the assumption that truth can be obtained through
sensory data and controlled experiments.
Coherence – this view is characterized with the logical way in which
relationships and judgment connect. According to this view if the proposition is
sufficient for today, then there is truth in it. (Meleis, 1999)
Pragmatism – this view is not dependent on evidence alone. It confirms theories
through restructuring.
Philosophical pluralism
Fuzzy logic is compatible with philosophical pluralism and shares views with several
major philosophical thoughts within nursing. They are:
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Post-empiricism – tries to incorporate more flexible positions. No common
pattern is viewed as having relevance for every individual situation. No universal
laws governing all of health are believed to exist.
Pragmatism – viewed as a way of dong philosophy that provides major
implications to solve disputes involving nursing science, theory and practice.
Feminism – highlights women’s diverse situations
Postmodernism – emerged against objectivity claimed in the academy that has
been the basis for modern western scholarship.
Conclusion
This paper presents fuzzy logic as a good example of a theoretical basis that
provides a method to deal with nursing issues and concepts that are vague and complex
and also with diversities that cannot be easily dealt with in an objective or subjective
manner. This paper proposes fuzzy logic as a new method that can be easily used in
some specific areas of nursing that can be characterized by vagueness, complexities and
diversities.