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David Souter

David Hackett Souter (born September 17, 1939) is an American lawyer and jurist who served as an associate justice of the U.S. Supreme Court from 1990 until his retirement in 2009. Appointed by President George H. W. Bush to fill the seat that had been vacated by William J. Brennan Jr., Souter sat on both the Rehnquist and the Roberts courts.

Raised in New England, Souter attended Harvard College, Magdalen College, Oxford, and Harvard Law School. After briefly working in private practice, he moved to public service. He served as a prosecutor (1966–1968) in the New Hampshire Attorney General's office (1968–1976), as the attorney general of New Hampshire (1976–1978), as an associate justice of the Superior Court of New Hampshire (1978–1983), as an associate justice of the New Hampshire Supreme Court (1983–1990), and briefly as a judge of the United States Court of Appeals for the First Circuit (1990).

Souter was nominated to the Supreme Court without a significant "paper trail" but was expected to be a conservative justice. Within a few years of his appointment, Souter moved towards the ideological center. He eventually came to vote reliably with the Court's liberal wing. In mid-2009, after Democrat Barack Obama took office as U.S. president, Souter announced his retirement from the Court; he was succeeded by Sonia Sotomayor. Souter has continued to hear cases by designation at the circuit court level.

Early life and education
Souter was born in Melrose, Massachusetts, on September 17, 1939, the only child of Joseph Alexander Souter (1904–1976) and Helen Adams (Hackett) Souter (1907–1995). His father was of Scottish ancestry and his mother of English ancestry. At age 11, he moved with his family to their farm in Weare, New Hampshire.

Souter graduated second in his class from Concord High School in 1957. He then attended Harvard University, graduating in 1961 with an Bachelor of Arts, magna cum laude, in philosophy and writing a senior thesis on the legal positivism of Supreme Court Justice Oliver Wendell Holmes Jr. While at Harvard, Souter was inducted into Phi Beta Kappa. He was selected as a Rhodes Scholar and earned a Bachelor of Arts degree (later promoted to a Master of Arts degree, as per tradition) in Jurisprudence from Magdalen College, Oxford, in 1963. He graduated in 1966 with a Bachelor of Laws degree from Harvard Law School.

Early career
In 1968, after two years as an associate at the law firm of Orr & Reno in Concord, New Hampshire, Souter realized he disliked private practice and began his career in public service by accepting a position as an Assistant Attorney General of New Hampshire. As Assistant Attorney General he prosecuted criminal cases in the courts. In 1971, Warren Rudman, then the Attorney General of New Hampshire, selected Souter to be the Deputy Attorney General. Souter succeeded Rudman as New Hampshire Attorney General in 1976.

In 1978, with the support of his friend Rudman, Souter was named an associate justice of the Superior Court of New Hampshire. As a judge on the Superior Court he heard cases in two counties and was noted for his tough sentencing. With four years of trial court experience, Souter was appointed to the New Hampshire Supreme Court as an associate justice in 1983.

Shortly after George H. W. Bush was sworn in as President, he nominated Souter for a seat on the United States Court of Appeals for the First Circuit. Souter had had seven years of judicial experience at the appellate level, four years at the trial court level, and ten years with the Attorney General's office. He was confirmed by unanimous consent of the Senate on April 27, 1990.

U.S. Supreme Court appointment
President George H. W. Bush originally considered nominating Clarence Thomas to Brennan's seat, but he and his advisers decided that Thomas did not yet have enough experience as a judge. Warren Rudman, who had since been elected to the U.S. Senate, and former New Hampshire Governor John H. Sununu, then Bush's chief of staff, suggested Souter, and were instrumental in his nomination and confirmation. Bush was reportedly "highly impressed by Souter's intellectual seriousness" and Souter's intellect, "particularly impressive in one-on-one meetings", was reported to have been a persuasive factor in his nomination. At the time, few observers outside New Hampshire knew who Souter was, although he had reportedly been on Reagan's short list of nominees for the Supreme Court seat held by Lewis F. Powell Jr. that eventually went to Anthony Kennedy.

Souter was seen as a "stealth justice" whose professional record in the state courts provoked no real controversy and provided a minimal "paper trail" on issues of U.S. Constitutional law. Bush saw the lack of a paper trail as an asset, because one of President Reagan's nominees, Robert Bork, had been rejected by the Senate partially because of his extensive written opinions on controversial issues. Bush nominated Souter on July 25, 1990, saying that he did not know Souter's stances on abortion, affirmative action, or other issues.

Senate confirmation hearings were held beginning on September 13, 1990. The National Organization for Women opposed Souter's nomination and held a rally outside the Senate during his confirmation hearings. The president of NOW, Molly Yard, testified that Souter would "end freedom for women in this country." Souter was also opposed by the NAACP, which urged its 500,000 members to write letters to their senators asking them to oppose the nomination. In Souter's opening statement before the Judiciary Committee of the Senate he summed up the lessons he had learned as a judge of the New Hampshire courts:

"The first lesson, simple as it is, is that whatever court we are in, whatever we are doing, whether we are in a trial court or an appellate court, at the end of our task some human being is going to be affected. Some human life is going to be changed in some way by what we do, whether we do it as trial judges or whether we do it as appellate judges, as far removed from the trial arena as it is possible to be. And so we had better use every power of our minds and our hearts and our beings to get those rulings right."

Despite the organized opposition, Souter won confirmation easily. Souter's performance at the confirmation hearings ensured his approval by the Senate; Walter Dellinger, a liberal Democrat and an adviser to the Senate Judiciary Committee, called Souter "the most intellectually impressive nominee I've ever seen". The Senate Judiciary Committee reported out the nomination by a vote of 13–1, and the Senate confirmed the nomination by a vote of 90–9; Souter was sworn into office shortly thereafter, on October 9, 1990.

The nine senators voting against Souter included Ted Kennedy and John Kerry from Souter's neighboring state of Massachusetts. These senators, along with seven others, painted Souter as a right-winger in the mold of Robert Bork.

U.S. Supreme Court

Souter opposed having cameras in the Supreme Court during oral arguments because he said questions would be taken out of context by the media and the proceedings would be politicized.

He also served as the Court's designated representative to Congress on at least one occasion, testifying before committees of that body about the Court's needs for additional funding to refurbish its building and for other projects.

Expected conservatism
At the time of Souter's appointment, John Sununu assured President Bush and conservatives that Souter would be a "home run" for conservatism. In his testimony before the Senate, he was thought by conservatives to be a strict constructionist on constitutional matters, but he portrayed himself as an incrementalist who disliked drastic change and attached a high importance to precedent. In the state attorney general's office and as a state Supreme Court judge, he had never been tested on matters of federal law.

After the appointment of Clarence Thomas, Souter moved toward the ideological middle. In the 1992 case Lee v. Weisman, Souter voted with the liberal wing and against allowing prayer at a high school graduation ceremony.

In the 1992 case Planned Parenthood v. Casey, Souter voted with the moderate wing in a majority decision in which the Court reaffirmed the essential holding in Roe v. Wade but narrowed its scope. Justice Anthony Kennedy had considered overturning Roe and upholding all the restrictions at issue in Casey. Souter considered upholding all the restrictions but was uneasy about overturning Roe. After consulting with O'Connor, the three (who came to be known as the "troika") developed a joint opinion that upheld all the restrictions in Casey except the mandatory notification of a husband while asserting the essential holding of Roe, that the Constitution protects the right to an abortion.

By the late 1990s, Souter began to align himself more with Stephen Breyer and Ruth Bader Ginsburg, although as of 1995, he sided on more occasions with the more liberal justice John Paul Stevens than either Breyer or Ginsburg, both Clinton appointees. On death penalty cases, workers' rights cases, defendants' rights cases, and other issues, Souter began increasingly voting with the Court's liberals, and later came to be considered part of the Court's liberal wing. Because of this, many conservatives view Souter's appointment an error of the Bush presidency. For example, after widespread speculation that President George W. Bush intended to appoint Alberto Gonzales—whose perceived views on affirmative action and abortion drew criticism—to the Court, some conservative Senate staffers popularized the slogan "Gonzales is Spanish for Souter".

A Wall Street Journal opinion piece ten years after Souter's nomination called Souter a "liberal jurist" and said that Rudman took "pride in recounting how he sold Mr. Souter to gullible White House Chief of Staff John Sununu as a confirmable conservative. Then they both sold the judge to President Bush, who wanted above all else to avoid a confirmation battle." Rudman wrote in his memoir that he had "suspected all along" that Souter would not "overturn activist liberal precedents." Sununu later said that he had "a lot of disappointment" in Souter's positions on the Court and would have preferred him to be more like Antonin Scalia. In contrast, President Bush said several years after Souter's appointment that he was proud of Souter's "outstanding" service and "outstanding intellect" and that Souter would "serve for years on the Court, and he will serve with honor always and with brilliance".

Planned Parenthood v. Casey
In the 1992 case Planned Parenthood v. Casey, the Supreme Court upheld the right to abortion as established by the "essential holding" of Roe v. Wade (1973) and issued as its "key judgment" the imposition of the undue burden standard when evaluating state-imposed restrictions on that right. The controlling plurality opinion in the case was joined by Souter, Kennedy and O'Connor. Souter is widely believed to have written the section of the opinion that addresses the issue of stare decisis and set out a four-part test in determining whether to overrule a prior decision. David Garrow later called that section "the most eloquent section of the opinion" and said it includes "two paragraphs that rank among the most memorable lines ever authored by an American jurist".

Bush v. Gore
In 2000, Souter voted along with three other justices in Bush v. Gore to allow the presidential election recount to continue, while the majority voted to end the recount. The decision allowed the declaration of George W. Bush as the winner of the election in Florida to stand.

In his 2007 book The Nine: Inside the Secret World of the Supreme Court, Jeffrey Toobin wrote of Souter's reaction to Bush v. Gore: "Toughened, or coarsened, by their worldly lives, the other dissenters could shrug and move on, but Souter couldn't. His whole life was being a judge. He came from a tradition where the independence of the judiciary was the foundation of the rule of law. And Souter believed Bush v. Gore mocked that tradition. His colleagues' actions were so transparently, so crudely partisan that Souter thought he might not be able to serve with them anymore. Souter seriously considered resigning. For many months, it was not at all clear whether he would remain as a justice. That the Court met in a city he loathed made the decision even harder. At the urging of a handful of close friends, he decided to stay on, but his attitude toward the Court was never the same. There were times when David Souter thought of Bush v. Gore and wept."

The above passage was disputed by Souter's longtime friend Warren Rudman. Rudman told the New Hampshire Union Leader that while Souter was discomfited by Bush v. Gore, it was not true that he had broken down into tears over it.

Relationship with other justices
Souter worked well with Sandra Day O'Connor and had a good relationship with both her and her husband during her days on the court. He generally had a good working relationship with every justice, but was particularly fond of Ruth Bader Ginsburg, and considered John Paul Stevens to be the "smartest" justice.

International recognition
Even though Souter had never traveled outside the United States during his years with the Supreme Court, he still gained significant recognition abroad. In 1995, a series of articles based on his written opinions and titled "Souter Court" was published by a Moscow legal journal, The Russian Justice. Those were followed by a book, written in Russian and bearing Souter's name in the title. Justice of the Constitutional Court of the Russian Federation Yury Danilov, reviewing the 2nd edition of the book in a Moscow English-language daily, made the following remark on Souter's position in Bush v. Gore: "In a most critical and delicate situation, David Souter had maintained the independence of his position and in this respect had become a symbol of the independence of the judiciary."

Retirement
Long before the election of President Obama, Souter had expressed a desire to leave Washington, D.C., and return to New Hampshire. The election of a Democratic president in 2008 may have made Souter more inclined to retire, but he did not want to create a situation in which there would be multiple vacancies at once. Souter apparently became satisfied that no other justices planned to retire at the end of the Supreme Court's term in June 2009. As a result, in mid-April 2009 he privately notified the White House of his intent to retire at the conclusion of that term. Souter sent Obama a retirement letter on May 1, effective at the start of the Supreme Court's 2009 summer recess. Later that day Obama made an unscheduled appearance during the daily White House press briefing to announce Souter's retirement. On May 26, 2009, Obama announced his nomination of federal appeals court judge Sonia Sotomayor. She was confirmed by the U.S. Senate on August 6.

On June 29, 2009, the last day of the Court's 2008–2009 term, Chief Justice Roberts read a letter to Souter that had been signed by all eight of his colleagues as well as retired Justice Sandra Day O'Connor, thanking him for his service, and Souter read a letter to his colleagues reciprocating their good wishes.

Souter's papers have been donated to the New Hampshire Historical Society and will not be made public until at least 50 years after his death.

Post-Supreme Court career
As a Supreme Court justice with retired status, Souter remains a judge and is entitled to sit by designation on lower courts. After his retirement from the Supreme Court and until 2020, he regularly sat by designation on panels of the First Circuit Court of Appeals, based in Boston and covering Maine, Massachusetts, Puerto Rico, Rhode Island, and his adopted home state of New Hampshire, generally in February or March of each year.

Souter has maintained a low public profile since retiring from the Supreme Court. In one exception, comments he made during a 2012 appearance at the Capitol Center for the Arts in New Hampshire about the dangers of "civic ignorance" were, in 2016, called "remarkably prescient" of the presidential campaign of Donald Trump.

Personal life
Once named by The Washington Post as one of Washington's 10 Most Eligible Bachelors, Souter has never married, though he was once engaged. He is an Episcopalian.

Souter was elected to the American Philosophical Society in 1994, and the American Academy of Arts and Sciences in 1997.

In 2004, Souter was mugged while jogging between his home and the Fort Lesley J. McNair Army Base in Washington, DC. He suffered minor injuries from the event, visiting the MedStar Washington Hospital Center for treatment. The problem led to public questioning of the Supreme Court Police's security detail, which was not present at the time.

According to Jeffrey Toobin's 2007 book The Nine, Souter has a decidedly low-tech lifestyle: He writes with a fountain pen, does not use email, and has no cellphone or answering machine. While serving on the Supreme Court, he preferred to drive back to New Hampshire for the summer, where he enjoyed mountain climbing. Souter has also done his own home repairs and is known for his daily lunch of an apple and unflavored yogurt.

Former Supreme Court correspondent Linda Greenhouse wrote of Souter: "to focus on his eccentricities—his daily lunch of yogurt and an apple, core and all; the absence of a computer in his personal office—is to miss the essence of a man who in fact is perfectly suited to his job, just not to its trappings. His polite but persistent questioning of lawyers who appear before the court displays his meticulous preparation and his mastery of the case at hand and the cases relevant to it. Far from being out of touch with the modern world, he has simply refused to surrender to it control over aspects of his own life that give him deep contentment: hiking, sailing, time with old friends, reading history."

In early August 2009, Souter moved from his family farmhouse in Weare to a Cape Cod-style single-floor house in nearby Hopkinton, New Hampshire, a town in Merrimack County northeast of Weare and immediately west of the state capital of Concord. Souter told a disappointed Weare neighbor that the two-story family farmhouse was not structurally sound enough to support the thousands of books he owns and that he wished to live on one level.

Over the years, Souter has served on hospital boards and civic committees. He is a former honorary co-chair of the We the People National Advisory Committee.

title: David Souter


text:
Talk:Many-worlds interpretation

Theory not mentioned here
Some scientists claim that when a solution results to many answers, all occur at the quantum level of the same universe, and when the first generation of these parallel solutions of a single wavefunction become involved in a new interaction, all the wavefunction collapses to the new point of least energy, and the secondary wavefunction expands from there, and it repeats the process again and again. So we have one universe with scouting wavefunctions (Feynmanism).

This is an extremely mainstream idea and we must analyze it better.

The word observation is erroneous, silly and romantic.

Matematically only percentages of strength of interactions exist. I compose poetry but it's a result of the memoremotional ( < memory + emotional ) limbic system, not of the analytical frontal lobe, neither a result of the mathematical parietal lobe.

Literature and alternate histories
I am minded to restore a trimmed down version of the literature section. It was culled with the comment that worlds split with quantum events, not human decisions - which is false since human decisions are quantum events, along with all other events. I have seen, on other platforms, people question whether alternate histories are actualized in MWI, even after reading this article. Clearly the point needs to be emphasized for the lay reader. cheers, Michael C. Price talk 10:41, 30 November 2023 (UTC)

 * I am not convinced that mainstream references actually support the following statement: All of the historical speculations entertained within the alternate history genre are realized in parallel universes[6], which seems very speculative. With quick reading, I did not find this in Refs.[6] either. The figure about a fictional history of the US also undermines the credibility of the article (and the theory). Jähmefyysikko (talk) 15:19, 30 November 2023 (UTC)
 * True, ref 97 is a better source for the claim. I'll move the ref.  See also Tegmark quote in the preceding section, which supports this.
 * The point about the "fictional" history of the US, is that it is not fictional in some Everett worlds, if we take the MWI seriously . cheers, Michael C. Price talk 16:34, 30 November 2023 (UTC)
 * I don't understand the phrase "genre are realized in parallel universes" in this sentence. I assume that what is meant is "genre occur in at least one of the infinite number of parallel universes."
 * The sentence, as it currently reads, is inappropriate. It states a fantasy as a fact, exactly the same as claims about religious miracles. Compare these sentences:
 * "The miracles of Jesus are miraculous deeds attributed to Jesus in Christian and Islamic texts."
 * "All of the historical speculations entertained within the alternate history genre are realized in parallel universes."
 * In the first sentence the encyclopedia carefully connects the extraordinary claim to the sources which make the claim. In the second sentence the miracles are stated a fact.
 * Similarly "Fictional histories which break the laws of physics (e.g. have magic) are not realised." makes an unverifiable claim as a fact.
 * The fact that such fictions exist and the nature of their content are notable. Statements claiming that such fictions are "realized" is WP:EXTRAORDINARY. Johnjbarton (talk) 17:08, 30 November 2023 (UTC)
 * Some "fantasy " as fact is exactly what Deutsch (and Tegmark) are claiming. Check out the Beginning of Infinity ref.  cheers, Michael C. Price talk 17:11, 30 November 2023 (UTC)
 * I agree with WP:EXTRAORDINARY. Tegmark quote is under 'speculative implications'. This should be placed there also, and attributed to Deutsch and Tegmark, not presented as an absolute truth.
 * The image caption includes too much WP:SYNTHESIS, and should be removed. The image is very rasterized and gaudy anyway. Jähmefyysikko (talk) 17:33, 30 November 2023 (UTC)
 * The whole point of the MWI is that a seemingly extraordinary fact (existence of parallel worlds or timelines) is true. This is why many people find the MWI absurd or incredible - but that can't be helped, it comes with the theory.  Which is precisely why the article needs to be explicit on this point.  cheers, Michael C. Price talk 17:37, 30 November 2023 (UTC)
 * It does not follow from the existence of parallel universes that for each fictional universe there would exists some microscopic realization, even if there are no imnediately apparent violations of physical laws. There might be more constraints on the realized universes than there are on the imagination of the writers. But it is all speculation, and if you claim otherwise, there should be stronger refs than Deutsch's semi-pop science book. Jähmefyysikko (talk) 18:00, 30 November 2023 (UTC)
 * In have given three strong references, all from professors of physics (Deutsch, Tegmark, DeWitt), so dismissing the idea as "semi-pop science" is not justified. cheers, Michael C. Price talk 19:28, 30 November 2023 (UTC)
 * The Beginning of Infinity is undeniably popular science. And as far as I can tell (the references aren't very specific), Tegmark and DeWitt do not talk about fictional universes, so using them as references is misleading. Jähmefyysikko (talk) 20:07, 30 November 2023 (UTC)
 * I changed the paragraph to attribute this point of view to Deutsch. Johnjbarton (talk) 22:32, 30 November 2023 (UTC)
 * Tegmark explicitly agrees with Deutsch, so this is not helpful. I shall restore the additional refs.  cheers, Michael C. Price talk 23:13, 30 November 2023 (UTC)
 * John Gribbin uses the example of Harry Potter as a magical work in fiction which is not realised, in his Royal Society award-winning book, Six Impossible Things. cheers, Michael C. Price talk 23:44, 30 November 2023 (UTC)
 * Besides, Deutsch is an advocate of MWI, and often makes very bold claims about it. Those cannot be taken to represent any kind of scientific consensus about the interpretation. Jähmefyysikko (talk) 20:15, 30 November 2023 (UTC)
 * Within the MWI community it is consensus. cheers, Michael C. Price talk 23:09, 30 November 2023 (UTC)
 * So far, we have only heard this claim from Deutsch. A slightly longer quote from Gribbin: Deutsch has pointed out that according to the MWI, any world described in a work of fiction, provided it obeys the laws of physics, really does exist somewhere in the Multiverse. There really is, for example, a Wuthering Heights world (but not a Harry Potter world).. Jähmefyysikko (talk) 07:55, 1 December 2023 (UTC)
 * No, the Wutherheights and Harry Potter is Gribbin's own synthesis. He is agreeing with Deutsch, but it is his own example.
 * Please don't use a topic merge as an excuse to delete such content again. It was in the article for years. I get that you think it "gaudy" - well let's try to improve it, not delete it. cheers, Michael C. Price talk 10:38, 1 December 2023 (UTC)
 * Gribbin devotes only half a paragraph of his popular science book for fictional universes. For the extreme interpretation that all alternative universes are realized in some branch, he cites Deutsch. The way I read it, he merely illustrates Deutsch's idea with Wuthering Heights and Harry Potter, and neither agrees or disagrees with him. In fact, since he says so little about the issue, citing him in support is WP:UNDUE weight.
 * And again, how are Refs. [6] (DeWitt) and [95] (Tegmark) relevant for the fictional universes? It seems incorrect to attribute such ideas to DeWitt and Tegmark, if they never explicitly articulated them. Please point out a specific place in the reference if I am wrong.
 * The fact that the figure you added in 2009 was in the article for some years after its initial addition is not really an argument for it, as it had also been absent from the article for multiple years now. The caption is original research (WP:IMAGEOR), as there is no source which states that Sobel's universe is realized in some branch of the Multiverse without WP:SYNTHESIS. If we remove the original research from the caption, the figure is not connected to the article. Why should we have it, when it is also very ugly? To improve its appearance would require it to be completely redrawn. Jähmefyysikko (talk) 13:27, 1 December 2023 (UTC)
 * I suggest you re-read WP:IMAGEOR, because it is explicitly encouraging editors to introduce images. "Original images created by a Wikipedian are not considered original research, so long as they do not illustrate or introduce unpublished ideas or arguments".  The idea here, of alternate histories being actualized, has been published, so that is really the end of the argument. Or are you going to argue that we can have an image based on Wuthering heights, but not for want of a nail? cheers, Michael C. Price talk 13:45, 1 December 2023 (UTC)
 * Yes, we could have Wuthering Heights, not as a fact, but as something attributed to Gribbin. For Sobel, we cannot do the same. Of course, neither is a good illustration of MWI. In the text, we would not invent our own example either. Jähmefyysikko (talk) 13:57, 1 December 2023 (UTC)
 * Also, following your suggestion, I reread WP:IMAGEOR. It says that captions are treated equally with the main text. Here the problem lies within the captions, not with the figure itself, which is fine to use in For Want of a Nail (novel), where it is not associated with MWI. Jähmefyysikko (talk) 14:50, 1 December 2023 (UTC)
 * And if you read the caption you will see that Sobel is not cited as an example of a MWI alternate history, but to illustrate the general point about the butterfly effect and branch points in history. It then goes on to say "everything" (explicitly following Tegmark and DeWitt) is covered by MWI, and it is left to the reader to connect the dots.  cheers, Michael C. Price talk 15:05, 1 December 2023 (UTC)
 * If one takes two unrelated statements and juxtaposes them in order to imply a conclusion not present in the sources, then this constitutes WP:SYNTH, even if the logical connection is not explicitly stated (but is obvious enough). And butterfly effect is not discussed in the article, so introducing it requires some reference. Jähmefyysikko (talk) 15:27, 1 December 2023 (UTC)
 * Actually I think what matters is whether the butterfly effect has ever been mentioned in the context of for want of a nail.
 * BTW, a Deutsch uses the examples of Roma Eterna and Fatherland. cheers, Michael C. Price talk 15:51, 1 December 2023 (UTC)
 * The word "butterfly" appears once in "For want of a nail : if Burgoyne had won at Saratoga" by Sobel, Robert, 1931:
 * ... Niles was “the best butterfly collector Mexico has ever seen, but this is no recommendation for the presidency.”
 * See https://archive.org/details/forwantofnailifb0000sobe/page/134/mode/2up?q=butterfly Johnjbarton (talk) 16:44, 1 December 2023 (UTC)
 * https://tvtropes.org/pmwiki/pmwiki.php/Main/TheButterflyEffect cheers, Michael C. Price talk 17:14, 1 December 2023 (UTC)
 * One may also use the Ladyman & Ross reference to argue against the idea that all fictional universes would necessarily be realized. They say: So although on the Everett interpretation, there is more to reality than the actuality that meets the eye, it is still the case that the actual (in the non-indexical sense) universal wave function rules out some possibilities, and hence that not all the modal structure of the world is realized. So, even if some fictional universe would be allowed by the laws of physics, it is not necessarily contained in the actual universal wavefunction. Jähmefyysikko (talk) 13:42, 1 December 2023 (UTC)
 * The claims of MWI are untestable and therefore equivalent to miracles. We should present them similarly, independent of our personal opinions. Johnjbarton (talk) 18:14, 30 November 2023 (UTC)
 * The untestable claim is old and hackneyed, and dealt with elsewhere. cheers, Michael C. Price talk 19:31, 30 November 2023 (UTC)
 * I made this series of edits. I concur with many of the criticisms above. Having content about a specific work of fiction/alternate history is WP:OR and WP:UNDUE, giving credence to an unscientific claim that it could be real. I also reorganized the section to not have so many (now overlapping) subheadings and tiny separate paragraphs, and, crucially for this matter, adding a source from Sean M. Carroll in which he debunks the common misconception that human decisions can be thought of as quantum events, with equally existing worlds for each outcome. Crossroads -talk- 01:43, 18 February 2024 (UTC)
 * The edit comment " Ugh, not this 'MWI means some fiction is real' silliness again " indicates you are pushing your own views of absurdity and not going with the sources. Both Deutsch and Gribbin are claiming exactly that, namely that some fiction is realised in MWI.  The wholesale removal of the section without discussion is not justified.  cheers, Michael C. Price talk 04:07, 18 February 2024 (UTC)
 * I'll grant that my edit summary, in shock over seeing that map return, was a bit much, but to be clear, I did not remove that section entirely. I retained this: David Deutsch speculates in his book The Beginning of Infinity that some fiction, such as alternate history, could occur somewhere in the multiverse, as long as it is consistent with the laws of physics.[92][93]. Anything more than this is undue weight - this idea exists solely as a rather brief mention in two popular-science works and both times is attributed to one man (Deutsch); it is not a scientific discovery or consensus in the peer-reviewed literature or even found there at all. It is those latter sources Wikipedia articles usually go by. Gribbin, as stated above by another editor, appears to simply be repeating and explaining Deutsch's idea without necessarily endorsing it - he specifically attributes the idea to him. In addition, as made clear by Ladyman and Ross, and Carroll (as mentioned above), just because humans can imagine something being plausible on a very coarse level doesn't mean it's actually consistent with the universal wavefunction. Given these factors, I think adding the one sentence I quoted is more than fair, but beyond that is undue (and relating the map to this topic remains OR in any case). Crossroads -talk- 23:57, 18 February 2024 (UTC)
 * Good discussion and I agree. Johnjbarton (talk) 01:27, 19 February 2024 (UTC)

The butterfly effect claim is WP:OR
The current article makes this claim in the caption for a figure:

A map from Robert Sobel's novel For Want of a Nail, an artistic illustration of how the butterfly effect – in this example the branching or point of divergence from our timeline's history is in October 1777 – can profoundly alter the course of history.

The connection between this classical effect in nonlinear systems and the branching in the many-worlds interpretation of quantum mechanics is not referenced.

Here is a contrary reference: “The Quantum Butterfly Noneffect” in SA Space & Physics Vol. 3 No. 6 (December 2020) "A familiar concept from chaos theory turns out to work differently in the quantum world."

Now there may be scientific work showing that MWI's model matches the butterfly effect, in which case both points of view could be represented. To me such a presentation of opposing points of view belong in quantum chaos or butterfly effect. Johnjbarton (talk) 03:47, 1 December 2023 (UTC)

 * Irrelevant to the effect on macroscopic, non-linear history. As they say, "To what extent the no-butterfly effect might apply in the macroscopic world of our lives is an open question,"  cheers, Michael C. Price talk 04:07, 1 December 2023 (UTC)
 * Ok let's check your reference. Oh, you don't have one. So we have no idea if there is any connection between the butterfly effect and MWI other than your personal assertion. Johnjbarton (talk) 16:46, 1 December 2023 (UTC)
 * I've re-removed the picture and caption; more explanation in the "Literature and alternate histories" section above. Crossroads -talk- 01:39, 18 February 2024 (UTC)

Feynman: equivocal or disinterested?
The "Equivocal" section begins with Ladyman and Ross weighing the pros and cons of MWI. This makes sense as an example of "equivocal". But the Feynman paragraph is not similar. It has two references. One is a pseudo-science book that cites an unpublished poll supposedly by a political scientist, L David Rabi. (The poll reports Gell-Mann as giving the same answer as Feynman, but Gell-Mann is not a Yes.) Two is an offhand remark by Feynman commenting on someone else's interest. The section quoted starts out: "In fact the physicists have no good point of view. Somebody mumbled something about a many-world picture, and that many-world picture says that the wave function ~ is what's real, ... It's possible, but I'm not very happy with it. So, I would like to see if there's some other way out,..." Does that sound like "yes" or even weighing the idea pro/con?

Richard Feynman publish many books on QM and discussed QM in many public lectures: he had plenty of opportunity to discuss MWI but did not. James Gleick never mentions Everett or MWI in "Genius: The Life and Science of Richard Feynman." Gleick mentions that Feynman rarely read other peoples work. Feynman was passionately interested in his own views of quantum mechanics. Rather than equivocal Feynman was disinterested. Johnjbarton (talk) 16:52, 3 December 2023 (UTC)

 * Feynman also at least once rejected the notion of 'universal wavefunction' when Wheeler brought up the Everett interpretation up in the 1957 Chapel Hill conference. (Chapel Hill report, p.270) But since it is just a single remark, I wouldn't use this to put him into the 'Rejection' bin either. I agree that we do not need to invoke Feynman here if he did not write anything about this topic. Jähmefyysikko (talk) 17:27, 3 December 2023 (UTC)

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title: Talk:Many-worlds interpretation