Here's what I've got this week from How to Live Safely in a Science Fictional Universe by Charles Yu:
Diegetical: In a diegetic manner or way [Oh, that helps...onward to...]
Diegetic: Of or relating to diegesis [Now I understand completely...]
Diegesis: A narration or recitation
Context: A man, as the theory goes, falling through time at a constant rate of acceleration, will not, absent any visual or other contextual clues, be able to distinguish between (i) acceleration caused by a force that is diegetical in nature and (ii) an extra-diegetical force.
Um. Okay. Do we all understand now? This is on page 33...I'm still trying to settle into the book and see if I like it. There have been some very interesting and some very funny lines, but overall I'm a bit lost.