Hi. I've been following your posts in this thread, and I hope you wouldn't mind answering a question. Also, pardon me if it seems that I am misrepresenting your position, I'm just trying to clarify.
You keep asking whether a variety of principles (e.g. the speed of light) are verifiable by the average person. Are you suggesting that if a discovery or principle of this nature is not verifiable by a person of average intelligence and education, then it is, on its face, invalid? If so, why?
No. What I submit is that we operate a great deal more on the basis of faith than we do on certitude. We trust propositions made to us by science without testing for ourselves whether the statements are true. With respect to the speed of light, that is something science can observe in the present day, though it only treats of one small aspect of light. Even in the matter of the speed of light, the average person lacks the tools and intelligence to measure it.