What is the grammatical "logic" of the impersonal construction with psychological verbs like pudet, piget, paenitet, taedet, miseret? (here is a short descriptive characterization of so-called “psych verbs” (in English))? A couple of typical examples follow:
Me non solum piget stultitiae meae sed etiam pudet. (Cic. De Dom. 29)
Sunt homines quos libidinis infamiaeque suae neque pudeat neque taedeat. (Cic. Verr. I, 1, 35)
Why is the experiencer object marked with accusative rather than with dative? (e.g., cf. Italian: A me mi importa solo di questo. Gloss: 'To me (dative!) matters only of this'. Translation: ‘Only this matters to me’). As for the genitive case, I guess that such an unexpected marking could be related to that of other mental verbs like memini. Many years ago I read (unfortunately, now I can’t remember the reference) that psychological verbs in Indo-European were basically denominal (i.e., derived from nouns), which in fact makes sense (e.g., in some languages something like “I fear ghosts” is expressed by means of a locative construction with the psych emotion being expressed with a noun: “the fear towards ghosts is (placed) in me”. Irish is an example of these languages).
Assuming that the Latin psychological verbs at issue are denominal, I was wondering if the genitive case could be explained by claiming that it is actually modifying the noun incorporated in the verb. But what about the accusative case of the experiencer object? In principle, it is a bit surprising since accusative marking of the object would typically require having a semantic/meaningful (i.e., non-expletive) subject in the sentence: e.g., cf. so-called ‘Burzio’s Generalization’. Notice that the Latin examples at issue (unlike examples with dative experiencer like Hoc mihi placet or with accusative experiencer like Hoc me delectat) can be regarded as involving an intriguing violation of this linguistic generalization. In this impersonal construction the verb does not assign a semantic function to its subject but it does assign accusative case to its object.
Another curious well-known fact of these verbs is that the construction is not impersonal if the subject is a pronoun (e.g., Non te haec pudent? Ter. Adelph., 754) or a clause or an infinitive (e.g., Me, mi Pomponi, valde paenitet vivere. Cic. Att. 3,4). As for the latter example, I was wondering why a gerund in genitive case could not instead be used here: e.g., Me paenitet vivendi.