the slippery "F" word - my solution

[Amethyst]

Here's my example. Say there is an island with no contact of the outside world. The island teaches every child from birth onward that the sky is purple. Now, the sky happens to be really blue.

False analogy, in this case they are simply using a different label to describe the same thing, neither of them is wrong because the world 'blue' does not have any more inherent value in describing the colour of the sky than the word 'purple' does, it's only a label than points to a concept.

As long as the concept is agreed upon, ie the wavelength of light captured by the eyes interpreted by the brain, what they name the concept is only a linguistic obstacle for communication and not an instance of them being right or wrong.

Not really, because one believes the sky is one thing, despite proof being offered it is something else, and the other believes it is another. This is like what Christians do when you debate with them and offer them logical evidence that they are wrong.

I'm not talking about interpretation of wavelength of light. I'm talking about being stubborn and saying something is one thing, when one has been offered logic that it cannot be that thing, such as what I like to call Biblegod.

If one was offered evidence that their dad was really dressing up as Santa, but still continued to believe in Santa literally, it's what Christians do.

As a child going to a Christian school, I was told from kindergarten and up, that a sky daddy existed. I believed such for years. Until I stopped being indoctrinated on a regular basis, I did not question the existence of the sky daddy. This is what happens with a lot of people.