In my last post I covered the basics of comparing regular adjectives. Participles decline as regular adjectives when they are compared, whether they be present active (patiēns, patient) or perfect passive (apertus, open).
A related phenomenon occurs with compound adjectives ending in -dicus, -volus, and -ficus (from dīcō, volō, and faciō). These compounds in fact take the stem of their related present active participle (dīcens, volens, faciens) in place of other endings.
The verbal stem –essō (rarely -issō) may be grafted onto existing verbs to denote a certain energy or eagerness of action (though not necessarily repetition.)
Capiō (take) —> capessō (snatch)
Faciō (do) —> facessō (do eagerly)
Petō (seek) —> petissō (look frantically for)
Declension of such verbs is usually third declension for present and infinitive, but fourth declension for perfect and supine.
Capessō, capessere, capessīvī, capessītum
Petissō, petissere, petissīvī, petissītum
This is somehow related to the rare variant of the future perfect stem -āssō.
amāssis (for ameris)
although these forms are so rare that there’s no complete declension of any one verb in this form in all extant Latin literature, fragmentary appearances suggest that these too would follow the third (present, infinitive) / fourth (perfect, supine) pattern
This post considers places where the Dative of Agent invades what would normally be constructions suitable to the Ablative of Agent.
With Passive Perfect Participles
With passive verbs, the Dative of Agent is most common with perfect passive participles, especially when these are virtually adjectival.
It has been deliberated and established by me: mihi dēlīberātum et cōnstitūtum est.
This has been provided for by you: tibi haec prōvīsa est.
The lights have made me dizzy: lūcibus cālīgātus sum.
Note that, with the final expression, lūcibus may be either Dative or an Ablative of Instrument (but not an Ablative of Agent, since there is no ā/ab). In this case, assume it’s an Ablative of Instrument, which is altogether more common, especially with something inanimate like ‘lights.’
– With Passive Verb
The Dative of Agent is not unheard of with standard passive verbs, especially with the poets.
He is not seen by anyone: nōn cernitur ūllī.
He was favored by the nymph: Nymphō fovēbātur.
The construction ‘it seems to x‘ is expressed with videor, vidērī, visus + Dative of Agent.
He seemed to me a horse with wings: mihi equis cum ālīs vidēbātur.
It seemed otherwise to the gods: dīs aliter vīsum est.
It seems to me that you are a slob: sordidus mihi vidēris.
According to AG, probāre takes a Dative of Reference, but it’s so regularly attached that it seems like a Dative of Agent. I’m not sure I buy this, but here’s what they mean:
This view was approved by both him and me: haec sententia et illī et mihi probābātur.
This plan was not approved by the majority: hōc cōnsilium plēris nōn probābātur.
The perfect infinitive used with verbs of feeling denotes a completed action.
Nōn paenitēbat intercapēdinem scrībendī fēcisse: It was no pain to take respite from writing.
Mē Graecum dixisse pudet: I am ashamed that I spoke Greek.
Illīs pira ēdisse iuvat: They’re pleased to have eaten pears
This pattern also holds with phrases like satis est, satis habēre, melius est, and contentus esse.
Satis est sōlem vidisse: it is enough to have seen the sun.
Quiēsse erit melius: it would have been better to shut up.
In sum, I should not that this is a grammatical preference, not a grammatical rule. You’ll encounter it frequently, especially in the poets, but verbs of feeling and these constructions do not demand the perfect infinitive.