The expression of obligation in Cicero’s De officiis

Modality, understood as a language category determining the speaker’s attitude towards the communicated content, can be divided into several types. One of them is deontic modality which relates to the notions of permission and obligation. The speech acts by means of which a speaker imposes an obligation upon the addressee are called directives. A speaker can express the necessity of realization of a state of affairs by addressee explicitly, refering to him directly, or implicitly, by means of the general expressions which lack an explicit agent. These general expressions may constitute directives only under specific conditions, first of all when the expression is marked by a present or a future tense and when the deontic source of the obligation and the addressee are indicated in some way. In Cicero’s De officiis explicit directives are realised with morphological means, such as the imperative mood, the first person plural subjunctive, the second person singular and first person plural future indicative, and with lexical ones: the performative verbs postulo and hortor. Whereas implicit directives are expressed by morphological means: the third person subjunctive and the third person future indicative, by lexical markers: the modal verbs debere and oportet, the impersonal phrases officium est and munus est, and by syntactic means: the periphrastic gerundival construction and the est + genetivus possessivus construction. However particular markers much differ with respect to their frequency in chosen corpus.This article attempts to distinguish various language markers of obligation used in Cicero’s De officiis. The tentative list of means which serve to express obligation in chosen text includes (1) morphological markers, such as: the imperative and subjunctive moods, the future tense; (2) lexical means: the modal verbs debere and oportet, the impersonal phrases officium est and munus est, the performative verbs postulo and hortor, and (3) syntactic markers: the periphrastic gerundival construction and the est + genetivus possessivus construction. However all these grammatical and lexical means may express the notions of deontic necessity only under the specific circumstances