I was curious to know which testers who blog, speak, write are philosophical. This may not be formal philosophy. Here is my initial list:
James Bach - I think he first introduced philosophy into thinking about testing. He refers to many formal concepts.
Michael Bolton - I see him more interested in social sciences. However, his writing and speaking is definitely philosophical.
Cem Kaner - Cem doesn’t seem to get deep into philosophy or sociology. However, from his book and speaking - his answers reflect a deep philosophy of testing.
G. Weinberg - again doesn’t get into ideology. However, his anecdotal style of writing shows a deep experience in working with testers and developers and understanding people.
Pradeep S - likes story telling and has an Asian/Indian flavor
Jeff Nyman - gets really into technical concepts
Here are a few more:
Huib Schoots, Jon Bach, Maaret P., Keith Klain
You can contrast this with others who don’t really get into ‘why testing’, ‘what is testing’ (let’s not name them - it’s not important).
P.S. I just found a way around the 20 character minimum post limit.
PPS. I think that most testers talk or write about some elements of basic philosophy in their work. Science can be traced to natural philosophy. Much of it is applied epistemology. The renaissance of testing came about because of an application of modern scientific principles and more historic philosophical ones (Karl Popper, David Hume, Immanuel Kant, Descartes, Moore, Locke, and so on).
Interestingly, going way back to my student days as a wannabe librarian, we had one module called “Organisation of Knowledge”, and the first year of that was all about epistemology. Our lecturer was a big adherent of Popper and Descartes before getting into the more specialist classifiers such as Dewey (who lots of people have heard of) and Ranganathan (who few have).
Clearly the connections between testing and scientific investigation are apparent to this group. Here are a couple of recent books on the philosophical implications of twentieth century science. You may find them of interest.
Physics Today has a very positive review of Exact Thinking in Demented Times: The Vienna Circle and the Epic Quest for the Foundations of Science, by Karl Sigmund. Karl Popper and other modern thinkers are included in the review. https://physicstoday.scitation.org/doi/10.1063/PT.3.3949
I recommend The Cellular Automaton Interpretation of Quantum Mechanics, by Gerard 't Hooft also. (Gerard 't Hooft shared the 1999 Nobel Prize in Physics for elucidating the quantum structure of electroweak interactions.) The book is available as a free PDF via the link below. ‘t Hooft’s interpretation deals with the unfortunate implications of the Copenhagen interpretation, like so-called action at a distance, and the collapse of the wave function. The conclusions in chapter 10 are a good summary. It includes a prediction on the feasibility of quantum computers as well. https://arxiv.org/abs/1405.1548
I would never expect to be mentioned in the same vein as the people you listed, however I have written some testing articles that touch on philosophical topics, notably poststructuralism and Hegelian dialectic.