Without looking it up, just take a wild guess: which world capital city is also the most common given name or surname that people have?

That’s a state capital, not a world capital, as defined by being the capital city of a country.
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Woops. 

Leave it to me to post on answerMug after a long day and evening of work, including four straight hours of sitting in the yard pulling weeds.

I say give him partial credit.  It’s possible but maybe not probable in the future.

 

  The question is about world capitals that already exist, it is not about predicting the future.
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Oh, but there’s a loophole. The Republic of Texas was a sovereign nation from declaring its independence from Mexico in 1836 until being admitted to the US as a state in 1845. This post was edited by Stu Spelling Bee at May 29, 2023 7:27 AM MDT

In the middle of the night, I'll try again  - - Sofia.

 

  It’s just an opinion question, so answers to it are not dependent upon my perspective. Thank you, though. I had not considered that it seems to be a specific or concrete answer.
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Yeah, the 'without looking it up' made it seem (to me) to be something one could look up. 

I wonder how long I'll wonder about this now. 

:P

Google is everyone’s friend. You can look up anything you can think of.

Google is no one's friend. 

 

  “I wonder how long I'll wonder about this now. 

:P“

  Yes, I guess it’s yet another way I’ve kept you from being able to get a good night’s sleep.  

  (Wait, that didn’t come out the way I meant for it to. Grrrrrrr.)
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Sorry to disappoint, but this will go into the 'things I wonder about whilst driving 90 minutes on a highway with almost no traffic' file. 

Please don't take this as a challenge. Hehe. 

 

 I feel more comfortable envisioning you in the way I alluded to previously.

Being stuck in traffic isn’t sexy enough.

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How it is an opinion question? 

 

  Because it’s asking for what one thinks as opposed to what one can investigate or verify to be 100% accurate. In order to answer a question like this with absolute certainty, it would take research, analysis, delving into statistics about the 198 countries that exist today plus the countries that used to exist, plus the names of capital cities that have changed over time. Additionally, all the world‘s languages contribute to the given names and the surnames that have existed throughout history. 

  It’s highly unlikely that anyone around here knows ALL of that information off the top of his or her head, and knowing this group of members, even iif someone responded as such, others might challenge the answers by stating they’re incorrect in some ways. One source of information could be limited to a certain time period or certain languages or certain parts of the world or be outdated, for example, and other members might say, “What about this . . . ?” or “You’re excluding this . . . “
Of the answers so far, things like that have already begun to happen, see for yourself.

  None of that is what I sought when posting the question, so I framed it specifically in a way that avoids the necessity of trying to get an exact or nearly exact answer; just a wild guess like I put in the parameter.

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But there are population records with people's surnames and records of the different nation's capital names. So there is indeed a correct answer to this question. It is not simply an opinion question.  

 

  Sigh. Once again, I am asking for opinions, not for records or what can be gleaned from records. I gave you a detailed and precise explanation of that in response to the exact question that you asked, and apparently you ignored it completely, and now you present an argument that the exact opposite of what I meant is what you think you mean. I will reiterate and expand, but it might not mean much to you: I am not stating that an exact answer does not exist, I am saying that I just wanted to know what members guess or surmise.

  Listen, if you want to post your own question on the same or similar subject matter in the way that you think is better than mine, please do so. Nothing stops you from topping me on this. 

Just because you asked for guesses does not change a fact question into an opinion question.  
Not trying to "top you" on this.  But it is not an opinion question just because you do not believe anyone knows the factual answer.

So when someone asks what is the answer to the question, it the answer is not that it is an opinion question, the answer is "I do not know."

 

  “. . . just take a wild guess . . .”

That’s how.
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