I knew a married couple who were very active in this cult. Their son was a friend of mine and was always rolling his eyes and leaving the room anytime his father and mother tried to "tag-team" me into reading their ridiculous "Bible".

I actually sought out skeptical literature about their belief systems and thus had an iron-clad defense from their silly, illogical cult. (Thanks you, Martin Gardner)

The more they explained their nonsensical beliefs, the more I realized the amount of disconnect from reality they must have had to buy-into this crap.

My question is this (and it applies to all cultic thinking) how is it that seemingly intelligent people can get swept up into ridiculous ideas when normal life experience and a high school knowledge of science should have made them laugh at nonsense of the situation?

I am reading the Martin Gardner book now and finding it incredibly interesting, to say the least. My cursory knowledge of the UB already had me thinking "how do people believe this," but of course people already believe a bunch of nonsense in other religious movements/text (so I'm not surprised).

In regards to your question, I've been reading The Wrong Way Home by Dr. Arthur J Deikman, which addresses this conundrum (why do intelligent people with normally perceived life experiences get involved in cults, etc.). I definitely recommend reading this; in it he also documents the lives of a well-educated married couple who got swept up in one.

Besides reading the UB and trying to get you to read it, did these parents of your friend have other odd behavior that you can associate with their belief and proselytizing of it?