It is nice to see such articles from you after a long time.
It is not even disputable: Karpov would DEFINITELY WIN in 1975

Pre-supposing all of those who disputed it were unbiased, the reason they dispute it is they estimate based on what might have been, not what actually were.
Looking at Fischer's 70-72 run, they make their disputed over Fischer 70-72 VS Karpov 74-75. But the reality was there was no longer Fischer 72. It was 75, unprepared and practiceless Fischer vs very dynamic, very prepared, motivated, dominating and concentrated Karpov.
Those who dispute it dismiss all these parts of reality and fantasise on their imagination.

Karpov himself said that he likely would've lost to Fischer in a 1975 match. He thought Fischer was still better than him even at that time. And these guys at that level know a bit about chess, preparation for chess competition, etc. He said this after many title matches, much analysis of games, many years of honest and thorough thought. Also, Fischer had already done a long retirement from all competition and came back even stronger than when he quit. Pal Benko had gave Fischer his spot in the interzonals just to get Fischer to play and Fischer was still slapping everyone off the chess board. I think Fischer's next opponents opinion, Anatoly Karpov, should be given the most weight.
But maybe you know more than Karpov, I don't know.
"Those who dispute it dismiss all these parts of reality and fantasise on their imagination."
"If you only knew how pompous and foolish you sound!
The only opponent that could defeat Fischer then was Fischer himself.
He refused to play Candidates' tournaments after the Soviet players colluded against him at Curaçao 1962. FIDE changed to Candidates' Matches as a result.
He withdrew from the Sousse Interzonal 1967 while leading bacause of some dispute.
He played no chess in 1969.
He refused to play the US Nationals over some dispute. As this was a zonal tournament so he could only play and win the Palma de Mallorca Interzonal 1970 as Pal Benkö gave up his spot.
He almost did not show up for the World Championship match at Reykjavik 1972.
He almost flew back home after the 1st game and forfeited the 2nd game.

Karpov himself said that he likely would've lost to Fischer in a 1975 match. He thought Fischer was still better than him even at that time. And these guys at that level know a bit about chess, preparation for chess competition, etc. He said this after many title matches, much analysis of games, many years of honest and thorough thought. Also, Fischer had already done a long retirement from all competition and came back even stronger than when he quit. Pal Benko had gave Fischer his spot in the interzonals just to get Fischer to play and Fischer was still slapping everyone off the chess board. I think Fischer's next opponents opinion, Anatoly Karpov, should be given the most weight.
But maybe you know more than Karpov, I don't know.
There is a thing called "humbleness". Of course I am not an oracle to state Karpov was saying what was not in his mind. Not everyone is like Fischer who at 15-20 yold keeps on asserting "I can beat the world champ Botvinnik. I can beat the women's world chess champ giving her knight odds" or who at 64 yold assertts "If I played chess, obviously I would be the best."
If you ask Kasparov now "If Fischer played on till 1987 would you beat him at that time?". He would say "Yes" outright, because people no longer want to seem assertive and self-promoting, self-advertizing.
But in 1988 for example young Garry Kasparov was similarly assertive, upon asking about Fischer he just dismissed the myth of Fischer stating "let him come and play a tournament. then we can talk."
Fischer is a champion that had a social image of highest repute, stating "I would almost certianly beat him in 1975" would make Karpov an arrogant person in many people's eyes.
But put the question in unrelated-to-people way and ask the same situation like: What if Kasparov quit chess for 3 years, did not study, was unprepared, had 2 months to prepare against world number 2 and played a world championship match? Everyone will just pick the world number #2.
It is the mythological status Fischer had that made things outrightly un-speakable. As for his earlier retirements and comebacks: in all those years Fischer was working on chess, he was analysing, he was publishing, he was following the latest developments. But on the case of Karpov, Fischer was not looking at chess board at all. He was just travelling, living his lost childhood and reading books.

It's not even disputable: Those "would...if" threads that pop up here now and then are laughable.
The only what if here is Fischer accepting to play the match on the deadline. No fantasy like "what if he kept on playing actively after the 72 match?" or "what if time travel was invented, then Fischer 72 met Karpov 81?"
Karpov did not want to play a 10-win match. All of his contemporaries agree that one of his major weaknesses was his physical stamina, which is reflected in several of his matches
Karpov defeated Spassky 7 - 4.
https://www.chessgames.com/perl/chess.pl?tid=84844
Fischer defeated Spassky 12.5 - 8.5

Karpov did not want to play a 10-win match. All of his contemporaries agree that one of his major weaknesses was his physical stamina, which is reflected in several of his matches
Karpov DID want to play Fischer under Fischer's terms. For the official match, Karpov consented to play under any match rules FIDE decided.
Then, it was Karpov who initiated the idea and negotiations of the private match, and he agreed to the rules Fischer dictated, including 10 wins. The only rule Karpov was unable to accept was the title of the match Fischer demanded: Absolute championship of chess PROFESSIONALS.
The reason he was unable to accept it was the fact that the Soviet government would not have allowed him to play the match because the Soviets did not recognise chess as profession. Karpov explained it to Fischer stating "My seniors will never allow me to play match with that name." Fischer at first seemed to have been persuaded, even took a pencil and the contract to sign but refused at the last moment.

Karpov defeated Spassky 7 - 4.
https://www.chessgames.com/perl/chess.pl?tid=84844
Fischer defeated Spassky 12.5 - 8.5
Spassky was actually superior in that match. To begin with, his long time assistant Geller switched to Karpov and as a result Spassky had to avoid playing his usual game and he had to come up with over-the-board power. He still won the first game despite playing ab opening he does not play in top level, playing an opening that was not used in top level. Later, He missed a win in a won game, then was no longer interested to win the match. After that, Karpov won 3 games

Remember that Fischer had played very little in the couple of years before his rampage through the candidates' matches and convincing world championship victory, so it's foolish to say "he wouldn't be prepared, couldn't play with top form" in 1975.
However, Fischer for all practical purposes retired in 1972. No matter what happened in 1975 he would have found some reason to abandon the match. He was psychologically unable to deal with ANY possibility of defeat and the destruction of his self-image as "the greatest".

Remember that Fischer had played very little in the couple of years before his rampage through the candidates' matches and convincing world championship victory, so it's foolish to say "he wouldn't be prepared, couldn't play with top form" in 1975.
The difference between his earlier retirees and the one after 72 is the fact that in his earlier retirees Fischer was still working on chess: He was publishing analysis, he was authoring books. He was aware of latest chessical developments whereas after 72 he just read religion books, travelled and experienced adventures he had not experienced before. He was completely alien to professional chess. Top 2 players playing and one of them being alien to the professional chess for 3 years? The other one will defeat him easily

Exactly. If Fischer ever had any intention of defending his title he would have continued to work on his game. Had he done so, he would have remained a formidable opponent. But Karpov had no chance to defeat Fischer because there was never going to be a match.

Exactly. If Fischer ever had any intention of defending his title he would have continued to work on his game. Had he done so, he would have remained a formidable opponent. But Karpov had no chance to defeat Fischer because there was never going to be a match.
Fischer refrained from everything, not just chess. He withdrew from writing books, he refrained from featuring in TV ads, he refrained from playing Gligorich, Korchnoi or any other person he himself would choose, all for at least a million dollar.
But still, to me he DID want to play Karpov but without compromising even one of his demands. As late as 1978, he was trying to use Korchnoi as go-between for his match negotiations against Karpov.
#15
"his long time assistant Geller switched to Karpov"
That is not accurate. Long time assistants of Spassky were Bondarevsky & Krogius. The Soviet Chess Federation ordered Geller to help Spassky against Fischer in 1972 because Geller was a strong theoretician and had a good score against Fischer. Geller prepared Spassky against the King's Indian and the Grünfeld, but Fischer wisely stayed away from those. Geller made Spassky play the Sicilian as black and prepared against Fischer's beloved 4 Bc4: game 4. Geller also made Spassky play the open Sicilian 3 d4 as white instead of his beloved closed sicilian 2 Nc3 and prepared against Fischer's favorite Poisoned Pawn Variation 7...Qb6 games 7 & 11. Geller even prepared Spassky in the Queen's Gambit Declined in the unlikely case Fischer would open 1 d4 instead of his usual 1 e4, and told him the move 14...Qb7!, but Spassky forgot in game 6.
After Spassky had failed to hold the World Championship title against Fischer, it is only logical that the Soviet Chess Federation put their hopes on their rising star Karpov to gain the title and thus ordered Geller to help Karpov.
#19
"without compromising even one of his demands"
This is the core of Fischer: no compromise neither on the chess board, nor aside of it.
Fischer was famous for playing on in theoretically drawn positions and even winning them e.g. against Geller in the Palma de Mallorca interzonal 1970.
He flew to the Lugano 1968 Olympiad to play board 1 of the USA, but he disliked the pieces, the chairs, the tables, the lighting. Organisers refused to meet his demands and Fischer flew home, renouncing his fee.
At the Sousse Interzonal 1967 he withdrew while leading because of some dispute.
Because of some dispute he refused to play the US Championship which counted as the zonal tournament and he only could play the Palma de Mallorca interzonal 1970 because Pal Benkö gave up his spot.
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In the past, I have written satirical 'treatise' countering Fischerphobs' conspiracies about Fischer being scared of Karpov. "Who would win Fischer or Karpov" is one of the most discussed topics on chess forums but I argue it is not even disputable: Karpov would have won in 1975.
I am not gonna evaluate based on what-ifs. I argue based on what were, not what c/would have been.
To do so, I look at Fischer's situation back in 1975 and prior to the aborted match. We can say the following from what is known about Bobby:
Now, what can be concluded from above? Considering Fischer declared his resignation in June 1974, he probably was not preparing for the match against Karpov. Considering he was travelling and reading history books since his match with Spassky, he probably was never prepared after the 72 match.
If FIDE somehow managed to persuade Fischer to play Karpov in 1975, Fischer would have entered the match without preparation and about 3 years of lack of practice. If Fischer consented to play match on the April of 1975, he would have 2 to 3 months to prepare against Karpov while Karpov was very active and well prepared with a chorus of experts on any field of chess.
The proponents of Fischer might say Karpov would have collapsed in a long match (supposing FIDE would have persuaded Fischer by granting him Cramer rules) whereas Fischer would endure but that is not a supportable assertion: We may support the Karpov part by pointing out his performance against Korchnoi - but that is baseless. We do not know if Karpov collapsed physically during that match. And we may not support the part about Fischer. We do not know if Fischer could endure a long match. After 11 games against Spassky, Fischer's game's quality decreased. One might say Fischer deliberately played passively to not risk his lead. Even if we agree with that, there is no basis to support the idea that Fischer would endure. We just do not know if Fischer could endure it, Fischer was not tested in that part. His prior matches in 71 run were sets of 6 matches, that is the longest he was tested. A decade earlier he played 11 games against Reshevsky. We just do not know if Fischer would endure - he just was not tested. Nor do we know if Karpov would collapse. The idea of Karpov collapsing in a long match might have come from his 1984 match against Karpov in which he bottled 5-0 win but his first loss came after 31 games + he was still fighting even after 40 games + according to what are written about the match, he ran out of chess preparation ideas, not his physical stamina.
Considering all of these, no matter how good Fischer had been in 71-72, he was unprepared after that. Karpov would definitely win.
Note: This post is not about "what if peak Fischer faced peak Karpov?" or "What if Fischer did not quit after 72, was active till 72 and faced Karpov?" or "What if Fischer did not resign in 74 but prepared to defend his title?" etc. It is about what actually were, not what might have been. The only hypothetical scenario here is Fischer acknowledging his participation on the 3rd of April, 1975 and faced Karpov.