# to convince someone of something



## quexavymz

This is more of a grammar question than anything.  What case would one use to translate "of something" in the phrase "to convince someone of something", with the meaning, "to convince someone that something exists".  One would think to use the genitive because of the use of "of", but I think it's more complicated than that.

Thoughts?


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## Lamb67

_Persuadeo_, plus dative of persons_ tibi_ for example, plus an infintive accusative constrution.


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## quexavymz

1) What do you mean by "dative of persons"?
2) What do you mean by an "infinitive accusative construction"?


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## Starfrown

quexavymz said:


> 1) What do you mean by "dative of persons"?


He means that the person being convinced is put in the dative case.



quexavymz said:


> 2) What do you mean by an "infinitive accusative construction"?


The accusative-infinitive construction features an infinitive with a subject in the accusative case.  It would be best to illustrate it with an example:

_Marcus mihi persuasit Caesarem tyrannum esse._
"Marcus convinced me that Caesar was a tyrant."

The dative is in green, the subject accusative is in red, and the infinitive is in blue.
----
Now back to your original request.  You asked how to translate "to convince someone of something."  While, as you say, the genitive might seem reasonable based on the English, in fact the accusative is used in the Latin translation:

_aliquid __alicui__ persuadere_

Although _persuadeo_, being intransitive, does not take an ordinary accusative object, it is common to see the accusative of neuter pronouns--and also perhaps of _res--_used with it in this way.


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## quexavymz

thank you!  Does that form of accusative have a name, or is it idiomatic?


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## Starfrown

quexavymz said:


> thank you!  Does that form of accusative have a name, or is it idiomatic?


I'm not sure exactly how it would be classified, and I suppose it's possible that different grammarians might treat it differently.

Note 145 on this page gives you a few more verbs that are similar to _persuadeo_ in their use.  (In this source, the author describes these verbs as usually intransitive, but transitive with the accusative of the "nearer object," which is not necessarily neuter.   If we follow this interpretation, there is no difference between the accusative with these verbs and the accusative of any other direct object.)


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## Imber Ranae

I've most often seen it classified as an internal accusative.

Another thing to keep in mind is that _persuadeo_, like many other verbs with similar meaning (_suadeo_, _moneo_, etc.), take either indirect statement (accusative + infinitive) or an object clause of purpose (_ut_ + subjunctive) depending on the exact significance. Indirect statement is used when persuading someone of a fact. Indirect command is used when persuading someone to do something.

_Ei persuasi magnum me esse._ "I convinced him that I am great." (indirect statement)
_Ei persuasi ut decederet._ "I convinced him to leave." (indirect command)

It's almost the exact opposite in English, interestingly.


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