Why didn't the Goblet of Fire refuse to choose a fourth participant?

Question

There were many names entered into the Goblet of Fire. The Goblet of Fire was designed to choose 3 participants from that list, one from each school. Maybe, it was a bug in the Goblet of Fire that kept it from validating the age requirement, but why did it choose a fourth candidate instead of rejecting him on the grounds that "All slots are filled"?

If Harry was chosen as the 1st, 2nd or 3rd one, it would be plausible. But, the Goblet of Fire chose Harry as the fourth, when each of the schools' slots were already filled.

How exactly was the "3 contestants, 1 per school" limitation overcome?

Answer 1

‘Because they hoodwinked a very powerful magical object!’ said Moody. ‘It would have needed an exceptionally strong Confundus Charm to bamboozle that Goblet into forgetting that only three schools compete in the Tournament ... I’m guessing they submitted Potter’s name under a fourth school, to make sure he was the only one in his category ...’ [Barty Crouch Jr/Mad-Eye Moody]

_{Goblet of Fire - page 245 - Bloomsbury - chapter 17, The Four Champions}

Thought about this when I was paging through Goblet of Fire recently and I kept coming back to one part. I see that CJM listed the passage in his answer that I'm going to quote; however, I'm putting it down again because I have a different take on that paragraph.

We already know Harry's name was added to the goblet by a second party; this is evident at the beginning of the book when Harry's name pops out of the cup to begin with.

I interpret Goblet of Fire canon to mean the primary element in Harry circumventing the powers of the Goblet of Fire is by someone first bewitched the goblet to forget it was to pick only three champions from three corresponding schools (which raises the issue of whether the goblet is sentient like the Sorting Hat is?). Forgetting is something a mind, a brain, does. The champions were not picked like a raffle; the Goblet of Fire chose champions based on, we might assume, merit, ability, intelligence, etc. So in some way it must think.

It is the act of forgetting that allows the Goblet of Fire to consider a fake entry as if it were legitimate, because it no longer knows the number of champions chosen should be limited to three.

Yes, Barty Crouch Jr put Harry Potter's name into the cup under a fourth school's name and that allowed Harry to be picked. However, if the goblet had never been forced to forget its own guidelines, it would have ignored that piece of paper with Harry's name and the fake school on it.

So, Sachin Shekkar's question is actually: The Goblet of Fire was designed to choose 3 participants from that list, one from each school? How exactly was the "3 contestants, 1 per school" limitation overcome? It was overcome because the goblet forgot it was supposed to limit itself. And this was achieved by Crouch Jr placing a very powerful Confundus Charm¹ on the goblet.

The Goblet of Fire had to be made to forget. It had to be made to forget it could choose only three champions from three schools. Placing Harry's name into the goblet is secondary to this -- it cannot happen unless the goblet first forgets its purpose and guidelines.

Yes, the goblet forgot how it works. Second to this -- and only second to this -- Crouch Jr was able to slip a piece of paper into the Goblet of Fire with Harry's name and the name of a fake school on it. Not remembering it could only choose three, the Goblet of Fire spat out Harry's name as the fourth Triwizard contestant.

¹_{I'm kind of scratching my head at the idea a Confundus Charm would cause the Goblet of Fire to forget. That particular power seems more consistent with a memory charm, or Obliviate. The Lexicon lists under Confundus Charm: "confundo" L. to mix up, jumble together, confuse, bewilder, perplex. Obliviate shows: "oblivisci" L. forget.}

Answer 2

Professor Moody explains in chapter 17:

“Because they hoodwinked a very powerful magical object!” said Moody. “It would have needed an exceptionally strong Confundus Charm to bamboozle that goblet into forgetting that only three schools compete in the tournament. . . . I’m guessing they submit­ted Potter’s name under a fourth school, to make sure he was the only one in his category. . . .”

And since Moody

(or rather Barty Crouch, who is disguised as Professor Moody at this point) is the one who actually did it, he should know. He repeats this in chapter 35, telling Harry, “Who put your name in the Goblet of Fire, under the name of a different school? I did.”

As for why it was done that way, the Goblet's primary job was to judge the potential contestants impartially and select the most worthy one from each school (see chapter 16). Corrupting that to ensure Harry was chosen as the Hogwarts champion would have been very difficult. Convincing it that a fourth school had opened since the last tournament was much easier. When you select one person from a list of one, there's not much judgment involved.

As for the minimum age requirement, that wasn't a function of the Goblet at all, but rather a spell that Dumbledore put around it. In chapter 16 again:

“To ensure that no underage student yields to temptation,” said Dumbledore, “I will be drawing an Age Line around the Goblet of Fire once it has been placed in the entrance hall. Nobody under the age of seventeen will be able to cross this line.”

Answer 3

What if the 3 school limitation was over looked upon the goblets creation? Yes, Moody says it was a charm. But perhaps he was mind over estimating his own ingenuity. The three school limitation was always limited by the organizers themselves. Of the 3 school lit was instead enforced by the ministry it may have been something that was overlooked upon creation. Moody may have tried a confundus charm and credited that as working but it was actually just a mistake left over from the creation. Therefore if there was never any instruction as to what to do when a fourth school is entered then it is plausible to believe that it would have seen the fourth school, pull the only name in that school and give it back.