Self-control -Reply

[Hans Blom, 950925]

So, Baumeister et al. have taken control theory and applied it to
the control of the self, and in particular to the self's behavior--a
lovely application, don't you think, Rick? Tom? Martin? Anyone? (;->

I don't know whether PCT offers an approach to these issues, but
control theory does, in particular the theory of multi-input multi-
output (MIMO) systems. The basics of this approach are as follows: 1)
a MIMO system has multiple goals; 2) in order to obtain a unique
solution, the number of goals must be equal to the number of outputs;
otherwise the system is under- or overconstrained (solutions are
possible in those cases, but they may become complex); NB: PCT also
takes this approach; 3) the actions required to achieve the goals are
usually non-orthogonal ("conflicting"), therefore fulfilling one goal
may hinder the achievement of the other; 4) the controller must know
the relative importance of its different goals.

It is the latter that sometimes offers some surprises: _redefining_
the relative importance of the goals may lead to _very_ different
action patterns. This seems to be counter-intuitive to us humans, who
seem to expect that small changes cause small differences; but simu-
lations show it readily. In engineering, an additional goal is often
to conserve energy/fuel/quantity of apllied drugs or what have you.
As an example, practice shows that a control law that takes energy
expenditure into account, even slightly, may save substantial amounts
of energy (say 30%) with almost no quality degradation (say -1%) in
goal achievement.

My two cents.