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A generalization of SDFW

We can generalize SDFW by applying preferences to actions rather than to the situations resulting from actions. The formulas then become

\end{array}\end{displaymath} (5)

(1) and

Choose\mbox{-}action(actor,a1,a2,s) =...
\textbf{then} a1 \textbf{else} a2.
\end{array}\end{displaymath} (6)

(5) and (6) obviously generalize (1) and (2), because the earlier case is obtained by writing

Prefers\mbox{-}action(a1,a2,s) \equiv Prefers(Result(a,s),Result(a2,s)).
\end{array}\end{displaymath} (7)

I am doubtful about the generalization, because I don't see how to represent commonsense preferences between actions except in terms of preferring one resulting situation to another.

John McCarthy