Figure 1: Graphical representation of a course of action.
A course of action is the path followed by an agent through its search space, from
its initial state to its (provisional) goal. The dotted arrow represents the
“straightforward” course that it would follow in the absence of diversions. The
full arrow represents its actual “meandering” course, which is affected by the
diversions encountered on the way: disturbances (dark grey triangles) to be
avoided, affordances (white ellipses) to be exploited and neutral diversions (light
grey rectangles) that merely push the course in a different direction.
Both affordances and disturbances are special cases of the more general notion
of diversion. A diversion can be defined as anything that makes an agent deviate from
its present course of action (see Fig. 1). Such diversion may be positive (affordance),
negative (disturbance), or neutral (general diversion). A diversion is positive when it
makes it easier than expected to achieve benefit. It is negative when it makes things
more difficult. It is neutral when it simply changes the situation in such a way that
you need to set out a new course of action, which is neither easier nor more difficult
than the previous one. For example, encountering a friend is an affordance;
encountering a foe is a disturbance; encountering a stranger is an initially neutral
diversion—which may turn out to be positive or negative depending on how the
stranger reacts to your actions.
Exploration and Exploitation
In general, disturbances are to be counteracted, affordances are to be exploited, and as
yet undetermined diversions are to be investigated or explored. This leads to a
generalization of the cybernetic notion of regulation: regulation can only suppress
diversions (or in the best case, when they are positive, allow them), and is therefore
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