What would you say? Part I

I'm currently taking a worldview class that's being taught by my brother Ben. I've taken it before, but the material is excellent, and always worth revisiting. Anyway, as per any worldview class, we take a look at other worldviews, and try to see how they got where they are. However, they can be boiled down into what we like to call the "Red Shirt Analogy." It all starts with someone trying to persuade another that a certain shirt is red...

It runs like this. The first person tries to convince the second person that the shirt is red. The second person contemplates it, and then accepts the statement, "This shirt is red." Presto, discussion over.

The second scenario is not the same. Here, the first person tries to convince the second that the shirt is red. However, the second person smiles sympathetically and proceeds to explain to the first that his (the first's) eyes have "a visual aid impairment wherein your retinal photosensitive ganglion cells that send signals along the retinohypothalamic tract to the suprachiasmatic nuclei and to the pretectal area to control pupillary light reflexes might be lacking the photopigment melanopsin..." and if you weren't lost before, you are lost now. Obviously, with all these big scientific terms, and the fact the second knew them, the first thinks the second an authority on the matter, and believes him instead (not so with Mr. J however!). After all, what would you say to a response like this?

The third scenario: the first tells the second "This shirt is red," to which the second replies "What shirt?" "Uh, this one, in my hands!" "What shirt?" "Right here, feel it?" "What shirt?" Obviously, the problem here is that the second doesn't even see the shirt, and in fact is in rejection of the shirt. He is, in a way, "blind to the shirt." How do you prove that a shirt is there? What would you say to these responses?

The fourth scenario is a profound example of denial. The first tells the second "This shirt is red." The second responds "No, it's blue." And then, despite the fact that he admits other similar colors to be red, the second still adamantly states "No, that shirt is blue." What do you say?