The Man Who Stole Infinity

https://fsolt.es/2026/03/the-man-who-stole-infinity/

How Can Infinity Come in Many Sizes?

https://fsolt.es/2026/03/how-can-infinity-come-in-many-sizes/

Cantor's proof that there are differently sized infinities changed math; it was also an act of plagiarism: "The Man Who Stole Infinity" @quantamagazine.bsky.social (Plus- Vallée Poussin)

Credit where credit's due: https://roughlydaily.com/2026/03/02/i-am-never-forget-the-day-i-first-meet-the-great-lobachevsky-in-one-word-he-told-me-secret-of-success-in-mathematics-plagiarize/

#cantor #culture #demiangoos #georgcantor #history #infinity #karinrichter #mathematics #pousin #primenumbertheorem #primenumbers #richarddedekind #science #tomlehrer #valleepousin

“I am never forget the day I first meet the great Lobachevsky. / In one word he told me secret of success in mathematics: / Plagiarize!”*…

In an 1874 paper, Georg Cantor proved that there are different sizes of infinity and changed math forever. But as Joseph Howlett reports, a trove of newly unearthed letters shows that it was also an act of plagiarism…

When Demian Goos followed Karin Richter into her office on March 12 of last year, the first thing he noticed was the bust. It sat atop a tall pedestal in the corner of the room, depicting a bald, elderly gentleman with a stoic countenance. Goos saw no trace of the anxious, lonely man who had obsessed him for over a year.

Instead, this was Georg Cantor as history saw him. An intellectual giant: steadfast, strong-willed, determined to bring about a mathematical revolution over the clamorous objections of his peers.

It was here, at the University of Halle in Germany, that Cantor launched his revolution 150 years ago. Here, in 1874, he published one of the most important papers in math’s 4,000-year history. That paper crystallized a concept that had long been viewed as a mathematical malignancy to be shunned at all costs: infinity. It forced mathematicians to question some of their longest-held assumptions, rocking mathematics to its very foundations. And it gave rise to a new field of study that would eventually bring about a rewriting of the entire subject.

Now Goos, a 35-year-old mathematician and journalist, had come to Halle — a five-hour train ride from his home in Mainz — to look at some letters from Cantor’s estate. He’d seen a scan of one and was pretty sure he knew what the others would say. But he wanted to see them in person.

Richter — who, like Cantor, had spent her entire career here, first as a research mathematician and then, after retiring, as a lecturer on the history of mathematics — gestured for Goos to sit. She lifted a thin blue binder from the scattered piles of books and papers on her desk. Inside were dozens of plastic sheet protectors, each one containing an old, handwritten letter.

Goos began flipping through, contemplating the letters with the relish of an archaeologist entering a long-lost tomb. Then he reached a particular page and froze. He struggled to catch his breath.

It wasn’t the handwriting. At this point in his research on Cantor, he’d become accustomed to the strange, nearly indecipherable Gothic script known as kurrentschrift, which Germans used until around 1900.

It wasn’t the signature. He knew that the German mathematician Richard Dedekind had been a key player in Cantor’s quest to understand infinity and solidify math’s foundations, and that the two had exchanged many letters.

It was the date: November 30, 1873.

He’d never seen this letter before. No one had. It was believed to be lost, destroyed in the tumult of World War II or perhaps by Cantor himself.

This was the letter that had the power to rewrite Cantor’s legacy. The letter that proved once and for all that Cantor’s famous 1874 paper, the one that would go on to reshape all of mathematics, had been an act of plagiarism…

The extraordinary story of unearthing this extraordinary story: “The Man Who Stole Infinity,” from @quantamagazine.bsky.social.

See also: “How Can Infinity Come in Many Sizes?“

* Tom Lehrer (not just a glorious songwriter, but also a gifted mathematician), “Lobachevsky” (referring to the mathematician Nikolai Ivanovich Lobachevsky— “not intended as a slur on [Lobachevsky’s] character [but chosen]”solely for prosodic reasons”)

###

As we confer credit where credit is due, we might spare a thought for Charles-Jean Étienne Gustave Nicolas, baron de la Vallée Poussin; he died on this date in 1962. A Belgian mathematician, he is best known for proving the prime number theorem (which formalized the intuitive idea that primes become less common as they become larger by precisely quantifying the rate at which this occurs). So great was the contribution that the King of Belgium ennobled him with the title of baron.

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I have the greatest admiration for the theorems and proofs of transfinite set theory, what we've called Cantor's transfinite set theory.

I taught it for years, wrote restatements for my students, and wrote a piece viewing it in the perspective of historical thinking about the infinite.
http://nrs.harvard.edu/urn-3:HUL.InstRepos:3715468

Now I've learned that #Cantor deliberately suppressed the role of #Dedekind in some of his work, particularly the proof that the set of real numbers is larger than the sets of natural and rational numbers. This was the first glimpse of the infinite hierarchy of infinite cardinalities.
https://www.quantamagazine.org/the-man-who-stole-infinity-20260225/

Cantor had the first germ of the proof, so props for that. But Dedekind helped him clarify it and Cantor published the clarified version without credit to Dedekind. I respect the math as much as ever but am now dealing with a serious case of flawed-hero syndrome.

First, make amends. Kudos to Dedekind. Second, give thanks. Kudos to the sleuths who turned up the empirical evidence of Cantor's #plagiarism -- Emmy Noether, Ivor Grattan-Guinness, José Ferreirós, and (decisively) Demian Goos.

Also thanks to Joseph Howlett for the Quanta article summarizing the evidence -- and in passing for calling Leopold #Kronecker an ideologue. Exactly!

#Infinity #Mathematics #SetTheory

To everyone who replied to my last post. thank you More than I can say. Knowing there are people out there who understand where I am coming from has lifted me in ways I did not expect. It is something I struggle with, and your kindness made a real difference. Welcome, also, to my new followers. I am glad you are here.

Today was my usual Saturday therapy appointment. Things are moving in a good direction. I have graduated to fortnightly sessions, which feels significant. After therapy I caught up with a friend, and came home with a new Victor Reader Stream 3. I am very much still in the "what does this button do" phase. My immediate goals are connecting it to my hearing aids via Bluetooth, getting it onto the wifi, tracking down all my favourite radio stations, and working out how to import my podcast subscriptions from Downcast. The good news is that Downcast can export an OPML file, and the Stream 3 has an "import podcast feeds from file" option in the podcasts menu, so that should be doable once I have the basics sorted.

Tomorrow is church. I am the cantor for the entire service, including the mass setting. It is the first time I have done the full thing from beginning to end. Meaningful does not quite cover it, but neither does terrifying. I only received the hymns and psalm list tonight, so my evening has been spent embossing everything and making sure I have it all ready. There is something grounding and nerve-wracking about that kind of preparation under pressure.

#BlindLife #DeafBlind #AssistiveTech #VictorReaderStream3 #Cantor #ChurchMusic #TherapyJourney #OPML #Downcast

"The Man Who Stole InfinityThe Man Who Stole Infinity"

#maths #cantor #infinity

https://www.quantamagazine.org/the-man-who-stole-infinity-20260225/

"From the days of #Miriam, the sister of #Moses and #Aaron, #Jewish #women have been leaders-without-portfolio. In the Book of #Exodus, Miriam, a “#prophetess,” leads the #Israelite women in song, but unlike Moses, the main recipient of teaching from God, and Aaron, the chief priest, she has no named role.

Today, women in many denominations of #Judaism are able to attend institutions of higher learning to become equipped with the necessary skills to gain credentials to be called #rabbi or #cantor. What will they do with their newfound titles? A crop of new #books and #TV #shows out this fall gives some answers."

https://religionnews.com/2025/11/19/in-new-memoirs-women-rabbis-wrestle-with-judaisms-male-centered-tradition/