Alt-history, whether personal or global, has always been both attractive and repellent to me. Those of us with memory or historical knowledge always have a host of just-barely or just-missed-it stories that lend themselves to fantasies of going back and changing one little thing. Sports fans, of course have dozens of such thoughts they can pop out on demand.
Yet I have always known it was a lie at deepest levels, not simply because to the inability to reverse time's direction, but because the very playing with the fantasy of One Little Change highlights how thoroughly the world could change with the merest tipping. The Arthur C. Clarke story of the man traveling back in time, killing a butterfly, and instantly vanishing I recognised as true immediately. If fact, I thought the death of the butterfly an excessive amount of interference for his illustration. Breathing on the butterfly or not would have been equally effective at changing the world. The story of Schrodinger's cat looks impossible, but there are truths about particles in it. And once particles have broken the seal, are any events exempt?
Reading Taleb, and a little cosmology, and reviewing Tom Stoppard's "Arcadia"* this week I will take that instability one step further. If we were to return to some early period and have time replay, the world would change dramatically even if we did not interfere in the slightest. The odds of some events are so close and the slippage so easy that a second iteration would turn out differently.
We don't imagine the world this way. We look at past events as having a certain inevitability, a narrative we can discern which explains things to us. Christians look to the first chapter of Jeremiah and cling pretty tightly to the hope that this knowing us from before the womb means what it looks like it does, but I am not sure it does. I think God is giving an "I know what I'm doing" message, not a "Let me give you a philosophy/science/cosmology lesson" one. (Not mutually exclusive, but it is good to keep the main point main.)
We swung pretty close to never existing, and still do to non-existence, held in suspension by a Logos that we understand in only the slightest way.
*Did I review that? Reminder to math/science geeks who have interest in theater. Stoppard is your go-to guy, right from the coin-flipping bit in "Rosencrantz and Guildenstern Are Dead" right up to, and especially including "Arcadia." None of this Obama-Tribe "Curvature of Constitutional Space" nonsense, misusing science concepts for social ends. Stoppard gets it. Thomasina in "Arcadia" is likely modeled on first-programmer Ada Lovelace.