It’s a thing of beauty, the ability to spin the cloth of reality, and you’re a sucker for it: Isn’t story-telling what being human is all about? - Charles Stross

You can do magic by hand, without computers, but magic performed by ritual without finite state automata in the loop—calculating machines, in other words—tends to be haphazard, unreliable, uncontrollable, prone to undesirable side effects, and difficult to repeat. It also tends to fuck with causality, the logical sequence of events, in a most alarming way.
We’ve unintentionally rewritten our history over the centuries, would-be sorcerers unwinding chaos and pinning down events with the dead hand of consistency—always tending towards a more stable ground state because chaos is unstable; entropy is magic’s great enemy. When the ancients wrote of gods and demons, they might well have been recording their real-life experiences--or they may have drunk too much mushroom tea: we have no way of knowing.

History is written by the survivors, a narrative they compose to explain events to themselves. So the historicity of journals like this one—their accuracy and authenticity—is a function of the reliability of the narrator.

They've sicced a demon on me."
"Jesus, Bob."
"Yeah, well, He isn't answering the phone."