An ultrafilter on is fine when it contains the set of small subsets containing , for each . Fineness makes every coordinate of represented in the corresponding ultrapower, though no one small subset is required to contain every coordinate.
An ultrafilter on is normal when each function with on a -large set is constant on a -large subset. This is the small-subset version of normality; together with fineness and kappa-completeness it gives the measure characterization of a supercompact cardinal.
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