Can a gerund have a predicative complement? By predicative complement I mean a complement which refers both to a noun or pronoun (the subject or the direct object) and to the verb, like e.g. "Peter came tired" or "Puer ludit laetus". Are phrases like "jus tacitus manendi" or "gratia tutus remanendi" correct in latin?
1 Answer
Generally speaking, in Classical Latin the nominative case cannot be licensed within a gerundial structure. So one can say Puer tacitus manet but not *Puer cupidus [manendi tacitus] (cf. ok Puer cupidus [manendi tacite], where tacite is an adverb).
A proviso must be made concerning some gerundial constructions in the ablative case that can be found in authors like Livy or Pliny, i.a. Note that an example like the following one could be said to be problematic for the generalization above against the licensing of the nominative case within the gerundial structure.
Non dissimilem offensionem et Aemiliani subiit L. Hostilius Mancinus, qui primus Carthaginem inruperat, situm eius oppugnationesque depictas proponendo in foro et ipse adsistens populo spectanti singula enarrando, qua comitate proximis comitiis consulatum adeptus est. (Plin. Nat. 35.23)
Transl. by Ida Östenberg (2009: 193): 'Also L. Hostilius Mancinus, who had first broken into Carthage, committed a very similar offence with Aemilianus by displaying in the Forum a painting of the site of the city and of the attacks upon it and by himself standing by it and describing the events one by one to the people watching. This was a piece of affable behaviour, which won him the consulship in the next election.'
However, it should be noted that the nominative case of ipse and of the present participle adsistens is licensed externally to the gerund enarrando (crucially in agreement with the subject of the main clause: L. Hostilius Mancinus), whereas the two arguments singula and populo spectanti are indeed internal to it, i.e. the latter are licensed within it: [ipse adsistens [populo spectanti singula enarrando]]. In any case, putting some technical complexity aside, this example can be said to be relevant here since it contains a participle (adsistens) that can be analyzed as a "predicative complement" (aka "secondary predicate") of the gerund enarrando.
In contrast to the nominative case, the accusative case can be more freely licensed within a gerundial structure, whereby the existence of examples that contain "predicative complements"/"secondary predicates" of gerunds is expected. For example, consider the following example:
Verum inlecebris Agrippinae, Germanici fratris sui filiae, per ius osculi et blanditiarum occasiones pellectus in amorem, subornauit proximo senatu qui censerent, cogendum se ad ducendum eam uxorem, quasi rei p. maxime interesset, dandamque ceteris ueniam talium coniugiorum, quae ad id tempus incesta habebantur. (Suet. Claud. 26.3).
Transl. from Loeb: 'But his affections were ensnared by the wiles of Agrippina, daughter of his brother Germanicus, aided by the right of exchanging kisses and the opportunities for endearments offered by their relationship; and at the next meeting of the senate he induced some of the members to propose that he be compelled to marry Agrippina, on the ground that it was for the interest of the State; also that others be allowed to contract similar marriages, which up to that time had been regarded as incestuous.'
Consider the constituent ad (prep.) ducendum (gerund) eam (sc. Agrippinam) uxorem ("predicative complement/secondary predicate/object complement"): 'to take her as his wife', i.e. 'to marry her'. Incidentally, it is worth noting that this example from Suetonius is also interesting because of these two reasons pointed out in this commentary: (i) the more classical construction is not the one used here ("preposition + gerund + direct object") but rather the one involving the gerundive (ad ducendam eam uxorem) and (ii) the ambiguous parsing/analysis of eam uxorem as 'this wife' or 'her (sc. Agrippina) as his wife'.
Unfortunately, as you can see, it is not unusual to cope with some syntactic complexity when looking for attested/real examples of very specific grammatical phenomena like the intriguing one you're interested in ("the existence of predicative complements/secondary predicates within a gerundial structure"). Putting this problem aside, I'd say that invented examples like the following one can be said to be possible.
cupidus ducendi Agrippinam uxorem ('desirous of taking Agrippina as his wife')