Blending margins: the modal logic K has nullary unification type
نویسنده
چکیده
We investigate properties of the formula p → 2p in the basic modal logic K. We show that K satisfies an infinitary weak variant of the rule of margins, which leads to a description of a complete set of unifiers of p → 2p. Using this information, we establish that K has nullary unification type. Moreover, we show that the formula p → 2p is admissibly saturated, but not exact.
منابع مشابه
Blending margins
We investigate properties of the formula p → 2p in the basic modal logic K. We show that K satisfies an infinitary weak variant of the rule of margins, which leads to a description of a complete set of unifiers of p → 2p. Using this information, we establish that K has nullary unification type. Moreover, we show that the formula p → 2p is admissibly saturated, but not exact.
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ورودعنوان ژورنال:
- J. Log. Comput.
دوره 25 شماره
صفحات -
تاریخ انتشار 2015