People can only See Things, they are already Familiar With

And by seeing, I am using the word in its broadest sense.

Take Mormonism, my family's religion. They were called Mormons, because their founder, Joseph Smith, wrote the Book of Mormon. When missionaries took this to England, the people there could see it was of divine origin - and that mean he was a Prophet of God! And they crossed the Atlantic Ocean, in vast numbers, to be with him.

No one bothered to count them - but there were a lot of them.

Their fellow-Americans did not bother to count them either - but they knew there was a lot of them. And they were different. And they did not like them.

As result, he was murdered by his fellow-Americans.