While visiting Half Price Books yesterday, I came across Alan Lightman’s Einstein’s Dreams (1993). Thumbing through it, I was reminded me of Eagleman’s Sum (2009) in that both are collections of witty, dream-like flash fiction tied to a common theme. Where Sum was a meditation on “the afterlives,” Einstein’s Dreams is an imaginative vision of worlds where, in one, cause does not precede effect and, in another, humans have no concept of the future and thus the present forever teeters on The End.
A person who cannot imagine the future is a person who cannot contemplate the results of his actions. Some are thus paralyzed into inaction. They lie in their beds through the day, wide awake but afraid to put on their clothes. They drink coffee and look at photographs. Others leap out of bed in the morning, unconcerned that each action leads into nothingness, unconcerned that they cannot plan out their lives. They live moment to moment, and each moment is full. 
With a prologue, three interludes, and an epilogue, the frame narrative for Lightman’s novel is a young Albert Einstein, 1905, having freshly completed his special theory of relativity. On the verge of shattering man’s sense of self and time, each of the thirty stories is a dream in the patent clerk’s head. Some are fantastic and others melancholic. Each causes the reader to pause, reread the last line, and take a deep breath. It’s as if one’s felt an ominous chill in their bones, so the chest tightens; the first flakes of winter confirm what the body already knew.
One particular story I enjoyed was “20 May 1905” (each are thus titled). In it there is no memory, and “A world without memory is a world of the present” where everyone is always seeing the world anew.
[E]ach woman returning from her job meets a husband, children, sofas, lamps, wallpaper, china patterns. Late at night, the wife and husband do not linger at the table to discuss the day’s activities, their children’s school, the bank account. Instead, they smile at one another, feel the warming blood, the ache between the legs as when they met the first time fifteen years ago. They find their bedroom, stumble past family photographs they do not recognize, and pass the night in lust. 
To navigate this world, everyone keeps a delicate record of their day-to-day activities called the Book of Life where they “can relearn the identity of his parents, whether he was born high or born low, whether he did well or did poorly in school, whether he has accomplished anything in his life.” Eventually it becomes so full that one cannot possibly read it in its entirety: either one “may read the early pages, to know themselves as youths; or they may read the end, to know themselves in later years.”
Some have stopped reading altogether. … They have decided that it matters not if yesterday they were rich or poor, educated or ignorant, proud or humble, in love or empty-hearted — no more than it matters how a soft wind gets into their hair. Such people look you directly in the eye and grip your hand firmly. Such people walk with the limber stride of their youth. Such people have learned how to live in a world without memory. 
What would you do?