Is Complexity A Metaphor Or Just A Muddle?
There were some interesting points in the series of articles on
complexity. The diabetes example from the second article in the series
(1) suggests the sort of results which the mathematics of chaotic systems
may be capable of when they are applied to healthcare. The point that
some things are not necessarily predictable even when they are described
quantitatively is a valuable one. Plsek and Wilson (2) develop this
further when they say that variation is inevitable in complex systems and
should therefore not always be considered to be a bad thing when we
encounter it in health: it is not a sign of failure which must be
eliminated. This is a timely reminder to be sceptical about a naïve
approach to variability, and becomes an important issue in health systems
with an emphasis upon performance indicators and league tables.
But some aspects of the series were less encouraging. There is a
persistently vague use of metaphor from the language of the physical
sciences. For example, ‘non-linear equation’ is a well defined concept
sometimes associated with complex properties such as sensitive dependence
upon initial conditions. But they don’t always go together (think of the
equation for a circle, for instance). Does ‘non-linear’ really apply to
story telling?(3) Sadly, I suspect that concepts from mathematics are
useful when applied mathematically, not as metaphors. The sheer use of
mathematical and physical terms does not alone lead us to knowledge: as
with any claim for insight the terms must be applied in a precise and
carefully reasoned fashion. Worse, such superficial use of metaphor can
distract from genuinely original ideas.
It is true that the mathematics of chaos is very generally
applicable. Even planetary motion, the paradigmatic example of a
predictable Newtonian system, has been found to be chaotic.(4) However
this example is a reminder that, like much else in physics, chaos is not
necessarily a direct antithesis to an earlier theory. A new way of
looking at phenomena doesn’t necessarily mean that everything we thought
before was wrong, which is why the Newtonian equations of gravity are
still good predictors of planetary motion for most practical purposes.
Chaos theory presents interesting new ways of understanding health
care, but we should not accept vague, unspecific metaphor and extravagant
claims that it holds all the answers in opposition to traditional
I have no competing interests.
1. Wilson T, Holt T, Greenhalgh T. Complexity science: Complexity and
clinical care. BMJ 2001;323(7314):685-688.
2. Plsek PE, Wilson T. Complexity science: Complexity, leadership,
and management in healthcare organisations. BMJ 2001;323(7315):746-749.
3. Fraser SW, Greenhalgh T. Complexity science: Coping with
complexity: educating for capability. BMJ 2001;323(7316):799-803.
4. Lissauer JJ. Chaotic motion in the Solar System. Reviews of Modern
Competing interests: No competing interests