We present a way of classifying the logically possible ways out of
Gärdenfors' inconsistency or triviality result on belief revision
with conditionals. For one of these ways—conditionals which are not
descriptive but which only have an inferential role as being given by the Ramsey
test—we determine which of the assumptions in three different
versions of Gärdenfors' theorem turn out to be false. This is done by
constructing ranked models in which such Ramsey-test conditionals are evaluated
and which are subject to natural postulates on belief revision and acceptability
sets for conditionals. Along the way we show that in contrast with what
Gärdenfors himself proposed, there is no dichotomy of the form:
either the Ramsey test has to be given up or the Preservation condition.
Instead, both of them follow from our postulates.
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