ศาลาชุมนุม

[Aulok]

I checked into the link of ท่านผู้นั้น, but unfortunately I failed to understand the explanation. Does it mean "someone" in a respectful way? It seems that this is a special phrase since it is necessary to gloss it in Wiki.

Could the word ท่าน be a respectful term preceding a person or a group of people? Like:
ท่านทั้งหลาย (literally: Dear All) "Ladies and Gentlemen"
ท่านทั้งปวง (literally: Dear All) ......
ท่านผู้หญิง (literally: Dear woman) "Lady, Madam"

Therefore, I guess ท่าน is simply a term to show additional respect: ท่านผู้นั้น (literally: Dear this person!) 'This person (who is respectable)'.

Then I know now that ผู้ is a classifier. Thanks!

[pensive]

ท่าน is just the formal version of คุณ. Therefore, ท่านทั้งหลาย is just คุณทั้งหลาย, but showing greater respect.

[Aulok]

ท่าน is just the formal version of คุณ. Therefore, ท่านทั้งหลาย is just คุณทั้งหลาย, but showing greater respect.

Thanks!! Then does คุณผู้นั้น make any sense? (This person)

[pensive]

I know nothing. I can imagine someone indicating a person in a crowd and saying to them คุณผู้นั้น ... in the sense of "That person there, ...(would you like to come up to the stage?)." But I'm just carrying English usage into Thai. You don't know, however, whether the meaning of ท่านผู้นี้ is intended.

[Tgeezer]

I know nothing. I can imagine someone indicating a person in a crowd and saying to them คุณผู้นั้น ... in the sense of "That person there, ...(would you like to come up to the stage?)." But I'm just carrying English usage into Thai. You don't know, however, whether the meaning of ท่านผู้นี้ is intended.

I think that in the website it is a name or title used in cartoons but I didn't really understand it but it is not ท่านผู้นี้ anyway.
Apart from that, as you said but putting it another way; ท่าน is a personal pronoun showing more respect. than คุณ You and เขา Him or her.
ท่าน as 'you' ; the subject of a sentence, doesn't need any amplification, ท่านผู้นี้ therefore must be 3rd person 'he, her-close by.
The big question is why ผู้ ? หลัง คน what we call a classifier. The answer would seem to be that if you want to distinguish a noun from all the others of the same type you must repeat it in some way, then amplify it.
The need to do this is the same in all languages the method is different. คนคนนี้ This person ผู้ชายคนนี้ This man.
ท่านผู้นี้ Him(with the greatest respect) ผู้ him ( less common than คน) นี้ here.
The problem is that if you say ท่านผู้นี้มีความสุข then ท่านผู้ฟังมีความสุข are you going to call ผู้ a classifier or a pronoun. I think that the answer is that you call them both สรรพนาม as in the RID.