I think I might be able to somehow "imagine" their mindset. I would say that surely these people who believed in, and probably saw, spirits of all shapes on a regular basis, "saw" the relatively silent sailing ship, but they obviously must have initially considered it to be a spirit of some sort, and initially deserving of the same level of attention that other such "spirits" normally received. As with other such "spirits," they probably were hoping and praying that if they ignored it, perhaps it would simply "go away," and leave them alone in peace.
Hey, I must confess I have actually "seen" some of these in my own day, and that is exactly how I tend to respond to most of them. As in a zoo with the sign, "don't feed the animals," most folks, when confronted with something that almost appears as a hallucination, will tend to try to "not feed" it.
However, should the "hallucination" begin to deploy longboats (much easier for a native to understand), and to begin heading in my direction with strangely colored and clothed men inside of them, you had better believe it, I would suddenly realize that my first strategy was simply not working, and I had better do something better, and quick!
Re: “Myth of the Invisible Ships”
PS: A further consideration.... If I were ever in some analogous circumstance, and if I were near others, I would probably do four things:
1. Question my own sanity.
2. Look around me to see if anyone else was seeing what I was seeing.
3. If nobody else seemed to see it, you figure out the rest.
4. Mayby, if I was brave enough, and a close family member had happened to be nearby when I thought I had the 'hallucination,' at the end of the day I might privately and carefully ask, "did you see what I saw?"
Kinda funny if you ask me :-)