We give a general approach to characterizing minimal information in a modal context. Our modal treatment can be used for many applications, but is especially relevant under epistemic interpretations of the operator square. Relative to a modal system S, we give three characterizations of minimality of a formula #phi# and give conditions under which these characterizations are equivalent. We then argue that rather than usign bisimulations, it is more appropriate to base information orders on Ehrenfeucht-Fraiesse games to come up with a satisfactory analysis of minimality. Moving to the realm of epistemic logics, we show that for one of these information orders almost all systems trivialize, i.e., either all or no formulas are honest. The other order is much mroe promising as it permits to minimize wrt positive knowledge. The resultign notion of minimality coincides with well-established accounts of minimal knowledge in S5. For S4 we comapre the two orders.
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