Yesterday I mentioned liking Greg Bear’s Judgement Engine, in Far Futures.  George Zebrowski has a similar story in the new Year Million.  Both stories describe extremely strange creatures and settings made familiar via disagreement.  Zebrowski:

There was a gathering. … The infalling ones argued that ours is worship of the unknown and unforeseeable, which amounts to a slavery no better than that of a humiliating existence in given natures, during the aeons when youthful intelligence did not know itself.  We replied that new hopes and further growth await us beyond the realm of passing localities, that an uncreated infinity sufficient to itself, can never be exhausted.  They might reshape, even engender new localities, but we will have to face the great mysterium of superspace.  We left them to their fates.

No matter what else is going on, it seems readers can relate to a story of two groups who argue over a claim and then break up unmoved.  It is as if we think this is one of the most reliable predictions we can make about intelligent creatures, no matter how otherwise strange.  If so, this shows just how radical is the claim that "rational" creatures would not knowingly disagree.

Added: Hal Finney lists other SF examples: