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                                   Goal-directedness

   Cybernetic or control systems are characterized by the fact that they have goals:
   states of affairs that they try to achieve and maintain, in spite of obstacles or
   perturbations
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   In the mechanistic world view, there is no place for purpose or
   goal-directedness. All mechanical processes are determined by their cause, which
   lies in the past. A goal, on the other hand, is something that determines a
   process, yet lies in the future. To a Newtonian scientist, the idea that an as
   yet non-existent, future state could influence the present, seems wholly
   unscientific, not to say mystical.

   The thesis that natural processes are determined by their future purpose is
   called teleology. It is closely associated with vitalism, the belief that life is
   animated by a vital force outside the material realm. Our mind is not an aimless
   mechanism; it is constantly planning ahead, solving problems, trying to achieve
   goals. How can we understand such goal-directedness without recourse to the
   doctrine of teleology?

   Probably the most important innovation of [2]cybernetics is its explanation of
   goal-directedness. An autonomous system, such as an organism, or a person, can be
   characterized by the fact that it pursues its own goals, resisting obstructions
   from the environment that would make it deviate from its preferred state of
   affairs. Thus, goal-directedness implies regulation of--or [3]control
   over--perturbations.

   A room in which the temperature is controlled by a thermostat is the classic
   simple example. The setting of the thermostat determines the preferred
   temperature or goal state. Perturbations may be caused by changes in the outside
   temperature, drafts, opening of windows or doors, etc. The task of the thermostat
   is to minimize the effects of such perturbations, and thus to keep the
   temperature as much as possible constant with respect to the target temperature.

   On the most fundamental level, the goal of an autonomous or autopoietic system is
   [4]survival, that is, maintenance of its essential organization. This goal has
   been built into all living systems by natural [5]selection: those that were not
   focused on survival have simply been eliminated. In addition to this primary
   goal, the system will have various subsidiary goals, such as keeping warm or
   finding food, that indirectly contribute to its survival. Artificial systems,
   such as thermostats and automatic pilots, are not autonomous: their primary goals
   are constructed in them by their designers. They are allopoietic: their function
   is to produce something other ("allo") than themselves.

   Goal-directedness can be understood most simply as suppression of deviations from
   an invariant goal state. In that respect, a goal is similar to a stable
   equilibrium, to which the system returns after any perturbation. Both
   goal-directedness and stability are characterized by equifinality: different
   initial states lead to the same final state, implying the destruction of
   [6]variety. What distinguishes them is that a stable system automatically returns
   to its equilibrium state, without performing any work or effort. But a
   goal-directed system must actively intervene to achieve and maintain its goal,
   which would not be an equilibrium otherwise.

   Control may appear essentially conservative, resisting all departures from a
   preferred state. But the net effect can be very dynamic or progressive, depending
   on the complexity of the goal. For example, if the goal is defined as the
   distance relative to a moving target, or the rate of increase of some quantity,
   then suppressing deviation from the goal implies constant change. A simple
   example is a heat-seeking missile attempting to reach a fast moving enemy plane.

   A system's "goal" can also be a subset of acceptable states, similar to an
   [7]attractor. The dimensions defining these states are called the essential
   variables, and they must be kept within a limited range compatible with the
   survival of the system. For example, a person's body temperature must be kept
   within a range of approximately 35-40 degrees C. Even more generally, the goal
   can be seen as a gradient, or "[8]fitness" function, defined on state space,
   which defines the degree of "[9]value" or "preference" of one state relative to
   another one. In the latter case, the problem of control becomes one of on-going
   optimization or maximization of fitness.

   Reference:
   Heylighen F. & Joslyn C. (2001): "[10]Cybernetics and Second Order Cybernetics",
   in: R.A. Meyers (ed.), Encyclopedia of Physical Science & Technology , Vol. 4
   (3rd ed.), (Academic Press, New York), p. 155-170
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   [11]Copyright© 2001 Principia Cybernetica - [12]Referencing this page

   Author
   F. [13]Heylighen, & C. [14]Joslyn,

   Date
   Aug 31, 2001 (modified)
   Sep 1991 (created)

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References

   1. LYNXIMGMAP:http://pespmc1.vub.ac.be/GOAL.html#PCP-header
   2. http://pespmc1.vub.ac.be/CYBERN.html
   3. http://pespmc1.vub.ac.be/CONTROL.html
   4. http://pespmc1.vub.ac.be/SURVIV.html
   5. http://pespmc1.vub.ac.be/SELECT.html
   6. http://pespmc1.vub.ac.be/VARIETY.html
   7. http://pespmc1.vub.ac.be/ATTRACTO.html
   8. http://pespmc1.vub.ac.be/FITNESS.html
   9. http://pespmc1.vub.ac.be/VALUES.html
  10. http://pespmc1.vub.ac.be/Papers/Cybernetics-EPST.pdf
  11. http://pespmc1.vub.ac.be/COPYR.html
  12. http://pespmc1.vub.ac.be/REFERPCP.html
  13. http://pespmc1.vub.ac.be/HEYL.html
  14. http://pespmc1.vub.ac.be/JOSLYN.html
  15. http://pespmc1.vub.ac.be/DEFAULT.html
  16. http://pespmc1.vub.ac.be/MSTT.html
  17. http://pespmc1.vub.ac.be/CYBERN.html
  18. http://pespmc1.vub.ac.be/CONTROL.html
  19. http://pespmc1.vub.ac.be/COMMUN.html
  20. http://pespmc1.vub.ac.be/REGUL.html
  21. http://pespmc1.vub.ac.be/MAKANNOT.html
  22. http://pespmc1.vub.ac.be/hypercard.acgi$annotform?

[USEMAP]
http://pespmc1.vub.ac.be/GOAL.html#PCP-header
   1. http://pespmc1.vub.ac.be/DEFAULT.html
   2. http://pespmc1.vub.ac.be/HOWWEB.html
   3. http://pcp.lanl.gov/GOAL.html
   4. http://pespmc1.vub.ac.be/GOAL.html
   5. http://pespmc1.vub.ac.be/SERVER.html
   6. http://pespmc1.vub.ac.be/hypercard.acgi$randomlink?searchstring=.html
   7. http://pespmc1.vub.ac.be/RECENT.html
   8. http://pespmc1.vub.ac.be/TOC.html#GOAL
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