[umanwizard]

FIDE arbiter guidelines, page 17:

> When a player places an inverted (upside–down) Rook on the promotion square and continues the game, the piece is considered as a Rook, even if he names it as a “Queen” or any other piece. If he moves the upside-down rook diagonally, it becomes an illegal move.

Link: https://arbiters.fide.com/wp-content/uploads/Publications/Ma...

This is not a philosophical question about metaphysics, where the rook’s true essence can be converted to that of a queen because really, what are the queens and rooks anyway but abstract symbols? The rook is the physical object that everyone in the tournament hall recognizes as a rook, which nobody has a problem identifying in practice.

[opello]

That's interesting, but I wonder if it's not more accurate to say "tradition doesn't support the use of an inverted rook as a promoted queen's proxy" or "FIDE would prefer not using inverted rooks as a promoted queen proxy" instead? Unfortunately neither explain why this is the preference, but avoiding ambiguity for observers seems obvious.

My thinking is that if we take "many active tournament players will see it every year or two" as the absence of a strict prohibition, and that this description of how it is illegal occurs in the "Arbiters' Manual," which self-describes as guidelines for arbiters and in the preface explains that rules can't cover every situation which is why the arbiters exist, but not in the actual rules document, it seems less "illegal" and more "unadvised."

I did not wax metaphysical, quite the opposite with the desire to find a definition for how one identifies a given piece. I imagine there are some other tournament organizational guidelines which outlines how chess sets are chosen for official events. These conventions taken in aggregate would provide some perspective, but still not answer the original question. I wager that everyone in your tournament hall would also recognize the use of an inverted rook as a promoted queen. So if it's not a question of avoiding ambiguity, then I wonder again, "why?"

There is a shorter version of this reply, which I will now include below:

At the end of the table of contents there is another interesting note in an offset grey box, just like the box which contains the note you quoted above:

> IMPORTANT:

> Throughout this manual, text which appears in a box such as this one is given as advice and is the opinion of a number of experienced arbiters. It does not form part of the Laws nor the Regulations in which it appears.

[umanwizard]

> That's interesting, but I wonder if it's not more accurate to say "tradition doesn't support the use of an inverted rook as a promoted queen's proxy" or "FIDE would prefer not using inverted rooks as a promoted queen proxy" instead?

No, it is against the FIDE rules. Both the official rules, and the unofficial explanatory text in the Arbiter's Manual. The official rules say that chess sets contain a piece called a queen, and a piece called a rook. They do not say anything about a piece other than a queen becoming a queen if it is turned in a different orientation, so it should be obvious that it doesn't do so.

But even for those for whom that wasn't obvious, there is additionally the arbiter's manual, explaining that yes, this is in fact the interpretation of the rules that FIDE and senior arbiters believe to be correct.

Despite all this you are refusing to believe it's actually against the rules. I am not sure what else I can cite to convince you. Google, ask your favorite LLM, or ask a FIDE arbiter if you want -- everyone will agree that if you promote to a rook, it is a rook, regardless of whether it's upside down or not.

Nobody has written a formal definition of which piece in a chess set is "the rook" and which one is "the queen", because the FIDE rules were not written by formal logicians, and so it probably never occurred to them that this was necessary.

This simply never comes up. You are probably the only person in history from the founding of FIDE until now who has pretended not to know what a rook or a queen is.

> My thinking is that if we take "many active tournament players will see it every year or two" as the absence of a strict prohibition

I think you are misinterpreting that comment. They are saying those players will see a scenario with two queens of one color on the board every year or two, not that they'll see someone trying to use an upside-down rook to stand for one of them.

[opello]

> They are saying those players will see a scenario with two queens of one color on the board every year or two

That makes sense.

It seems to me that you've used a lot of truism reasoning out of frustration. I tried to head these off with my original assumption that it was a question of identity.

>> I anticipate the argument being one of identity, such as "a rook is a rook whether it is right side up or upside down." This is an argument of convention.

Since the reliance is on convention, and an inverted rook is conventionally treated as a promoted queen, the FIDE Arbiters' Manual describes a policy of not following this convention. I'm sure someone knows why this is the guidance. I was curious about that reasoning. It seemed interesting and worthy of discussion.

> You are probably the only person in history from the founding of FIDE until now who has pretended not to know what a rook or a queen is.

You ascribe to pretend ignorance what is in fact interest in the history of a thing. This seems unreasonably antagonistic.

I believe you've misunderstood my original comment and I do not know why, but I think I will be done with this thread. If you find out why this was the adopted guidance for the FIDE Arbiters' Manual I'd enjoy reading about it and I imagine others may too, but it should be put under the original question, not here.

[umanwizard]

> Since the reliance is on convention, and an inverted rook is conventionally treated as a promoted queen

I think that convention is much less strong than the conventional meaning of the piece shapes. I have only seen it in casual games, and I’m not sure if it exists in every country.

I don’t know why this rule was adopted, but I gave a few plausible reasons off the top of my head in another post on this thread.