System Thinking in the UK

["JPK CRAWFORD" <jpkcrawford@btconnect.com>]

Vic Forte posed interesting questions about systems in the Digest V2002 #35
as follows:

"The intrinsic contradictions within systems seem to be these:

In order for a system to exist it must have a boundary. But this boundary is
not real - it is put there in order to help us to think about the system.
The system is inextricably bound up with the dynamics of the world outside
of itself. So are those within the boundary misled if they believe in it and
direct their efforts towards its survival ?"

Those are questions we constantly face in my field of system safety, so
here is a brief account of how we deal with them.

It hardly needs to be said that we have to be clear about exactly what
system we are specifying, designing, analysing, assessing, accepting into
service (or not), using and managing.    So defining the system boundaries
is an essential part of the job.  We do that mainly by reference to the aim
of the system.  The question "is this element a part of our system?" is
resolved by answering the question "does it contribute to the aim of the
system?"  My personal view is that there is nothing unreal about a boundary
so defined.   The boundary may often seem fuzzy at the edges, because some
of the components may also be components of other systems.  Some basic set
theory can be helpful here.

Yes of course every system interacts with other systems, and will also be a
component of some wider system(s).  So it will be involved in a network of
two-way interactions.  We deal with that aspect by treating the "inward"
interactions as the operating environment in which the system must work
during its service life.  The definition of that environment is an early and
important task, leading to decisions on design, testing and assessment.
Then there are the "outward" interactions, including the intended effect of
the system (the aim).  The potential for unintended effects has also to be
defined, again leading to decisions on design, testing and assessment.

To conclude, my answer to Vic's question is that those within the system
boundary are not misled if they believe in it and direct their efforts
towards its survival - I think they are doing some proper system thinking.
But if that is all that they do, I would say that they may not be doing the
whole job.

I would be interested to hear whether this is any help to anyone, and how
Vic's question is answered in other fields.

Best wishes,
Jack Crawford
jpk@crawfd.co.uk