The first story "Tlön, Uqbar, Orbis Tertius" can leave you scratching your head if you have no background of Borges nor have read much in the magical realism genre. However, upon reading once and feeling confused, read it a second time, and you many find yourself picking up on other details.
Borges is a master at succinct short stories that are truly philosophical. Instead of going on a philosophical rant of 300 pages, he chooses a few pages and a few choice words. If you haven't read much philosophy, this will be a struggle. If you have never heard of Schopenhauer, get a quick review. His work largely influenced Borges. You might as well get a quick review of Kant as well.
The word "labyrinth" and "time" reoccur throughout the stories, as well as the theme of fiction, the title of this collection. Many of the stories twist our conception of order and time, which are concepts we have placed on ourselves, rather than truly comprehending their meanings. Borges weaves these illogical notions into stories that irk our belief. For example, "The Secret Miracle," in which time stands still in the mind of a man about to be executed, seems impossible, but then again, how could anyone prove otherwise? Borges is wildly imaginative, but he does set rules, and nothing goes out of bounds.
I really enjoyed these short stories. I took my time to read through each one, often going back and re-reading parts. My favorites were "Pierre Menard, Author of the Quixote," "The Circular Ruins," "Funes the Memories," and "Death and the Compass."