Professional mathematician. Doctorate in (a subarea of) mathematics from a German university.

Germany
»..diligite homines, interficite errores, sine superbia de veritate praesumite, sine saevitia pro veritate certate, orate pro eis quos redarguitis atque convincitis.« St. #Augustine(354–430), Contra Litteras Petiliani, Book 1, Chapter 29 #Christianity #ChristianCulture #Europe
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#KreiselObituaryForGoedel-20 [Psychiatry Psychology] "After Gödel’s first visit to Princeton (1933/34) he had a nervous breakdown. It began with severe anxiety when he got off the boat. .. Wagner-Jauregg was called in, a Nobel Prize winner [then] more famous than Freud, >
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[Extremely relevant to the above: Wagner-Jauregg seeing Gödel is mentioned in the interview with Hao Wang and Robin Gandy (v=hnBSRxHDxBk).] > , at least in Austria. No indications of psychosis were found. >
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Logic Geometry, Information retweeted
Pohlers' valuable 1999 Proof-Theory-lecture notes appear to have vanished from uni-muenster.de/Logik/en/Stu… (and from the non-deep web in its entirey)! Today I managed to retrieve the pdf from the Internet Archive! One good deed a day. 😊
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To repeat myself: it is embarrassing (to humanity) that it is only ONE (freely accessible) internet-archive. It should go without saying that there ought to be several such archives on several continents. This kind of centralization is intolerable.
The internet's memory isn’t a cloud—it’s heat, power, and hard drives 🔥💾 Inside the Internet Archive’s trillion-page fight against digital forgetting, from PetaBox servers to legal battles over memory itself ⚙️📚 Learn more ⤵️ hackernoon.com/the-long-now-… @zbruceli #InternetArchive #DigitalPreservation #WebHistory #Infrastructure #Engineering
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Pohlers' valuable 1999 Proof-Theory-lecture notes appear to have vanished from uni-muenster.de/Logik/en/Stu… (and from the non-deep web in its entirey)! Today I managed to retrieve the pdf from the Internet Archive! One good deed a day. 😊
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#FefermanWhatLogicTellUs-1 [CoquandNeuwirth #KreiselObituaryForGoedel Outreach #TaitNoCounterexample Teaching] The Mathematical Intelligencer 2, pp. 20–24 (1979) What Does Logic Have to Tell us about Mathematical Proofs? Solomon Feferman (Stanford University)
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'Der Mensch ist ein der Idee nach Unendliches, das jeweils in endliche Bedingungen eingespannt ist und nur in diesen, indem es sie ergreift, Substanz gewinnt. [In] dieser [Lage] kommt es für jeden Menschen darauf an, in ihnen frei zu werden.' Jaspers: Idee der Universität (1961)
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#KreiselObituaryForGoedel-64 'In short, formalization and purity of method is just much subtler than suggested by generalities about mathematical rigour.. A corollary to this is that the significance of Gödel’s incompleteness theorem is a subtle business too. For if we were to >
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#KreiselObituaryForGoedel-63 "[It] is often neglected [that] (i) [the] actual reliability or ‘security’ [of impure proofs] is obviously unaffected by the possibility of pure proofs if that possibility has not been realized (ii) impure methods are not only used heuristically, >
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>, as..logical hygiene. But also there is the void created by simply not saying out loud what (knowledge) is gained by impure proofs, for example by analytic proofs in number theory: knowledge of RELATIONS BETWEEN THE NATURAL NUMBERS AND THE COMPLEX PLANE or, more fully, >
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>between arithmetic and geometric properties. It is precisely this knowledge which provides effective new means of checking proofs: if this conflicts with some ideal of rigour, so much the worse for the ideal (which is being tested)."
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Uhm, thanks...
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"Lindström had an exceptionally clear and concise style in writing mathematical logic. His 1997 book, Aspects of Incompleteness, remains a perfect example: it provides a systematic introduction to his work in arithmetic and interpretability. The book is short .." [Teaching]
#DawsonGoedelToLindstroem-1 [#LindstroemElementaryLogic #HistoryOfMathematics] History and #Philosophy of #Logic 14(1), 15-37 (1993) The Compactness of First-Order Logic: From Gödel to Lindström John W. Dawson, Jr. M.t. Die Kompaktheit der Logik erster Stufe: von Gödel bis >
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>of propositional logic) while in fact this inference requires the Substitution Lemma of of Modal Logic (which isn't hard but definitely nontrivial). Smoryński treats this lemma right in [9780387962092; p. 77]. The (admitted by Lindström) fact that he was copying this from >
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>Smoryński's book makes this expository error even more severe.
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It is a commonplace worth repeating that superhuman intellects have existed for a long time (and the world did not change dramatically because of it): any technical forum constitutes a superhuman intellect. Both they and putative machine-solutions have finite resources, too.
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(Similarly, any moderately disciplined research team is a superhuman intelligence, i.e., more intelligent than one human being.)
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new and relevant:
Broke: AI consciousness Woke: AI personhood Bespoke: Corporate personhood Bewoked: Corporate consciousness
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New and relevant:
Broke: AI consciousness Woke: AI personhood Bespoke: Corporate personhood Bewoked: Corporate consciousness
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"Fast allen Bildungsidealen ist gemeinsam der Sinn für - Disziplinierung - Form - Selbstbeherrschung" Karl Jaspers: Die Idee der Universität (1923)
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#KreiselObituaryForGoedel-62 "Defects of ideals are generally seen most clearly in areas where they have been realized, and so the results can be compared both with earlier expecta­tions and with alternatives >
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"the typesetter's nightmare is the reader's delight"
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