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.cb COUNTERFACTUALS, CARTESIAN PRODUCTS AND APPROXIMATE THEORIES


	The thesis of this paper is that counterfactual conditional
sentences take their meaning in approximate theories of some
phenomenon that have a Cartesian product structure.  If the world
or the next level of approximation does not have that structure,
then the meaningfulness of the counterfactual does not extend
beyond the approximate theory.  We start with an example.

	%2If I lived in Alaska, I would wear warmer clothes in winter
than I do here in California%1.  
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.begin verbatim
John McCarthy
Artificial Intelligence Laboratory
Computer Science Department
Stanford University
Stanford, California 94305

ARPANET: MCCARTHY@SU-AI
.end

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PUBbed at {time} on {date}.%1