Editing Paul Feyerabend (section)

====Kraft Circle, hidden variables, and no-go proofs====
During Feyerabend's PhD, he retrospectively describes himself as a "raving [[positivist]]."<ref>{{Cite book|last=Feyerabend|first=Paul K.|title=Against Method|year=1993|edition=3|pages=275}}</ref> He was the head organizer of the 'Kraft circle' which discussed many issues in the foundations of physics and on the nature of [[logical positivism#confirmation|basic statements]], which was the topic of his dissertation. In 1948, Feyerabend wrote a short paper in response to Schrödinger's paper "On the Peculiarity of the Scientific Worldview." Here, Feyerabend argued that Schrödinger's demand that scientific theories present are ''Anschaulich'' (i.e., intuitively visualizable) is too restrictive. Using the example of the development of Bohr's [[Bohr model|atomic theory]], he claims that theories that are originally unvisualizable develop new ways of making phenomena visualizable.<ref name=Feyerabend1948>{{cite journal|last=Feyerabend|first=Paul|title=The Concept of Intelligibility in Modern Physics |journal=Studies in History and Philosophy of Science Part A|volume=57|date=1948|pages= 1–3}}</ref> His unpublished paper, "Philosophers and the Physicists," argues for a naturalistic understanding of philosophy where philosophy is "petrified" without physics and physics is "liable to become dogmatic" without philosophy.<ref>{{Cite book|last1=Collodel|first1=Matteo|last2=Oberheim|first2=Eric|date=2020|title=Feyerabend's Formative Years|publisher=Springer Press|language=en|pages=475–6}}</ref>

Feyerabend's early career is also defined by a focus on technical issues within the [[philosophy of quantum mechanics]]. Feyerabend argues that [[John von Neumann|von Neumann's]] 'no-go' proof only shows that the [[Copenhagen interpretation]] is consistent with the fundamental theorems of quantum mechanics but it does not logically follow from them. Therefore, causal theories of quantum mechanics (like [[Bohmian mechanics]]) are not logically ruled out by von Neumann's proof.<ref name=Shaw20201>{{cite journal|last=Shaw |first=Jamie|title= The Revolt Against Rationalism: Feyerabend's Critical Philosophy |journal= Studies in History and Philosophy of Science Part A|volume=80|date=2020| pages= 113|doi=10.1016/j.shpsa.2019.05.007 |pmid=32383668 |bibcode=2020SHPSA..80..110S |s2cid=182010729 }}</ref> After meeting David Bohm in 1957, Feyerabend became an outspoken defender of Bohm's interpretation and argued that [[Hidden-variable theory|hidden variable]] approaches to quantum mechanics should be pursued to increase the testability of the Copenhagen Interpretation.<ref name=vanStrienl/>

Feyerabend also provided his own solution to the measurement problem in 1957, although he soon came to abandon this solution. He tries to show that von Neumann's measurement scheme can be made consistent without the [[collapse postulate]]. His solution anticipates later developments of [[quantum decoherence|decoherence theory]].<ref name=KFra>{{cite journal|last1=Kuby |first1=Daniel|last2=Fraser |first2=Patrick|title= Feyerabend on the Quantum Theory of Measurement: A Reassessment |journal= International Studies in the Philosophy of Science |date=2022|volume=35 | pages= 23–49|doi=10.1080/02698595.2022.2067811 |s2cid=251357846 |url=http://philsci-archive.pitt.edu/20036/1/kuby-fraser-feyerabend.pdf }}</ref>