Maybe somebody will try to prove molecules exist, based on what's available to them in their homes. (No, don't)
I think I must be a mass-less particle (I've been reading). Steve, you fail to take time into consideration. Many things aren't testable at the time someone asks the question.
How long was it between when someone posited the existence of molecules and proof of their existence? Telling people, before molecules were able to be observed, that the question of their existence shouldn't be asked, because the answer "has been deliberately put beyond scientific enquiry" is a little bit anti-science. And messed up. The methods to test theories often are found because of the questions.

That doesn't mean they will NEVER be questionable. People who are afraid of questions without answers are just as superstitious and anti-science as deists.

They are still afraid to admit they can't know...now.