

The reader familiar with C+ knows also that there is no syntactic
category of "inertial fluents" in that language.  The syntax of C+
distinguishes between two kinds of fluent constants -- simple and
statically determined.  If <i>C</i> is a simple fluent constant then<p>

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<tt>inertial</tt> <i>C</i>
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<p>is shorthand for the set of fluent dynamic laws<p>

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<tt>caused</tt> <i>C=V</i> <tt>if</tt> <i>C=V</i> <tt>after</tt> <i>C=V</i>
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<p>for all possible values <i>V</i> of <