Editing Frame problem (section)

===Default logic solution===
The frame problem can be thought of as the problem of formalizing the principle that, by default, "everything is presumed to remain in the state in which it is" ([[Gottfried Wilhelm Leibniz|Leibniz]], "An Introduction to a Secret Encyclopædia", ''c''. 1679).  This default, sometimes called the ''commonsense law of inertia'', was expressed by [[Raymond Reiter]] in [[default logic]]:

: <math>\frac{R(x,s)\; :\ R(x,\mathrm{do}(a,s))}{R(x,\mathrm{do}(a,s))}</math>

(if <math>R(x)</math> is true in situation <math>s</math>, and it can be assumed<ref>i.e., no contradicting information is known</ref> that <math>R(x)</math> remains true after executing action <math>a</math>, then we can conclude that <math>R(x)</math> remains true).

Steve Hanks and [[Drew McDermott]] argued, on the basis of their [[Yale shooting problem|Yale shooting]] example, that this solution to the frame problem is unsatisfactory.  Hudson Turner showed, however, that it works correctly in the presence of appropriate additional postulates.