(November 15, 2022 at 6:04 pm)R00tKiT Wrote:(November 6, 2022 at 12:49 pm)polymath257 Wrote: But there are times when absence of evidence *is* evidence of absence. For example, if I fail to detect an adult african elephant in my room, I can conclude that there is no adult african elephant in my room.
Nope, you can't, if you fail to detect elephants in your room, this just means you failed to detect them, nothing more. I mean, most accidents in life happen because people are hilariously bad at detecting things.......?
Besides, I can say the same thing about quarks, or electrons : I fail to detect any trace of quarks or electrons in my room, they have no distinguishable form, or smell, or color, or flavor, they're undetectable even if one uses the most sophisticated microscope available, and science tells us they're extremely small, very suspicious.... So I conclude there are no electrons and quarks in my room..
I'll anticipate one possible objection : you may say there are experiments that can be done to show electrons are real, but this is irrelevant in this context. You're telling us that you, personally -not experiments, or machines, or other people-, couldn't detect an elephant, and from that fact alone, you allowed yourself to come to the hasty conclusion that the elephant doesn't exist. This is obviously a mistake.
And again, the difference is that if there is an elephant in my room, I would detect it. That is why my non-detection is proof of non-existence.
If you had the correct equipment to detect an electron reliably and did not detect one, THEN you could reason that there is no electron.
Quote:(November 6, 2022 at 12:49 pm)polymath257 Wrote: But going deeper, if the detection is impossible even in principle, what does it even mean to say that something exists? I could then equally well argue that undetectable unicorns exist in my room. Who is to say otherwise?
If you provide plausible reasons for the unicorns existence -aside from detection-, then we have to assess these reasons on their own merits.
Some centuries ago, most discoveries in modern physics were completely undetectable, even in principle........
The plausible reasons for unicorns would all be based on some observations and the actual existence would not be demonstrated until the unicorns themselves were detected.
No, the discoveries of modern physics were NOT undetectable in principle. We simply didn't know enough to either suspect they could be done or how to do them. There is a huge difference between that and the type of undetectability proposed for deities and the supernatural. For the first, it is a matter of ignorance. For the latter, it is a matter of principle.