Terry Pratchett described substitions in his Discworld novel Jingo, as the opposite of superstitions. More specifically, he describes a superstition as "a thing that everyone believes in but nevertheless isn't true," and a substition as "something that is true, but hardly anyone believes in."

He goes on to mention that there are many such substitions, which include "It'll get better if you don't pick at it," "Sometimes things just happen," and "There are a lot of things in the world that you don't know about."

Terry Pratchett describes 71-Hour Ahmed as substitious, which "places him in a minority amongst humans." This is still true today. It's easy to read about Ahmed's acceptance of things he doesn't know about when we, the reader, know perfectly well what is going on, and quite another thing to face the unexpected in real life and yet have a realistic and rational attitude about it.