I’m making a separate reply for the betting thing, only to try to keep the two conversations clean/simple.
Let’s muddle through it: If I have a box containing an unknown (to you) number of gumballs and I claim that there are an odd number of gumballs, you would actually be quite reasonable in assigning a 50% chance to my claim being true.
If I claim that the gumballs in the box are blue, would you say there is a 50% chance of my claim being true?
What if I claimed that I ate pizza last night?
You might have a certain level of confidence in my accuracy and my reliability as a person to not lie to you; and, if someone was taking bets, you would probably bet on how likely I am to tell the truth, rather than assuming there was a 50% chance that I ate pizza last night.
If you you then notice that my friend, who was with me last night, claims that I in fact ate pasta, then you have to weigh their reliability against mine, and more importantly now you have to start looking for reasons that we came to different conclusions about the same dinner. And finally, you have to weigh the effort it takes to vet our claims against how much you really care what I ate last night.
So, assuming you are rational, would you bet 50⁄50 that I ate pizza? Or would you just say “I don’t know” and refuse to bet in the first place?
Do scientists think it works, or does it work? The end result is a model for a particular phenomenon which can be tested for accuracy. When we use a cell phone we are seeing the application of our understanding of electromagnetism, among other things. It’s not scientists saying that science works—it’s just working.