Even though the men at the dinner party were well educated men, in what ways were they ignorant?

The men who've gathered for dinner are all brilliant, intelligent men, who work at the top of their fields. Operative word being "fields". A doctor can see a body and evaluate a mind, but that does not mean he can imagine the ability to travel in time. I would consider these men to be educated realists without imagination. I would not consider them ignorant.