Stit-logic for Imperatives


G. V. Karpov


In this paper the possibility of interpreting imperatives as sentences that are used by rational agents to impel or motivate other rational agents to act in a desired way investigates by the author. We claim that such impelling strategies, that ground practical reasoning, can be pictured formally by means of stit-logic. We introduce the basic semantical ideas of stit-logic and discuss the most acceptable way of formal representation of imperative and its corresponding impelling effect. Special attention is paid to embedded stit-formulas. We demonstrate that such formulas cannot serve as an appropriate way of imperative formalization since an agent-addressee lacks the possibility of choice, and the agent-sender becomes “omnipotent” about the future course of agent-addressee’s action. We show that this unwanted situation can be eliminated, and basic imperative properties can still be expressed with embedded stit-formulas, if different kinds of indexes are used in semantic definitions for different kind of stit-operators. Finally we put an assertion that using such formulas, evaluated with respect to different kind of indexes, leaves no room for usual paradoxes of imperative logic.






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