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Two elaborations of the stuffy room scenario


The first elaboration says that when Pat finds the room stuffy he unblocks vent2. We have


or, more elaborately,


(24) remains the same except that perhaps we should change the notation so that instead of S3 and S3' we write S2'' and S2''', since these are now intermediate situations. The situation S4 is now unstable.

Now let's add a second elaboration in which Mike finds the room cold when there is an unblocked vent and blocks vent2. It is expressed by adding


With both of these elaborations, we get an oscillation; Pat unblocks vent2 and Mike blocks it again. tex2html_wrap_inline1121 and tex2html_wrap_inline1123 are no longer defined.

John McCarthy
Fri Feb 8 17:29:20 PST 2002