“The Hitch Hiker’s Guide to the Galaxy is an indispensable companion to all
those who are keen to make sense of life in an infinitely complex and confusing Universe, for though it cannot hope to be useful or informative on all matters,
it does at least make the reassuring claim, that where it is inaccurate it is at
least definitely inaccurate. In cases of major discrepancy it’s always reality
that’s got it wrong.
This was the gist of the notice. It said “The Guide is definitive. Reality is
frequently inaccurate.”