Vladimir Nabokov

In The Eye, Vladimir Nabokov speculates eloquently on changing a single event in one's past and tracking the cumulative effect of the resulting variations. (This theme was reworked in the episode "Time and Punishment" of The Simpsons.)
Nabokov emphasizes the branching structure of the changes in our lives, anticipating the bifurcation diagram of the logitic map.
Additionally, while some small changes can grow to have large effects, others appear to be truly inconsequential. The major states of our lives can be thought of as attractors, and all the events leading up to a given state may be viewed as the basin of attraction of the event. Changes that have large effects may be near the boundaries of basins of attraction, so we are led to the notion of fractal basin boundaries in history.
Here is Nabokov's description, from pgs 27-8 of The Eye.
It is silly to seek a basic law, even sillier to find it. Some mean-spirited little man decides that the whole course of humanity can be explained in terms of insidiously revolving signs of the zodiac or as the struggle between an empty and a stuffed belly; he hires a punctilious Philistine to act as Clio's clerk, and begins a wholesale trade in epochs and masses; and then woe to the private individuum, with his two poor u's, hallooing hopelessly amid the dense growth of economic causes. Luckily no such laws exist: a toothache will cost a battle, a drizzle cancel an insurrection. Everything is fluid, everything depends on chance, and all in vain were the efforts of that crabbed bourgeois in Victorian checkered trousers, author of Das Kapital, the fruit of insomnia and migraine. There is a titillating pleasure in looking back at the past and asking oneself, "What would have happened if ... " and substituting one chance occurrence for another, observing how, from a gray, barren, humdrum moment in one's life, there grows forth a marvelous rosy event that in reality had failed to flower. A mysterious thing, this branching structure of life: one senses in every past instant a parting of ways, a "thus" and an "otherwise," with innumerable dazzling zigzags bifurcating and trifurcating against the dark background of the past.