Every decision is the death of a thousand possibilities
Things came easy to you. They always had. You picked things up fast. School, especially the early years of it, was mostly a matter of waiting for everyone else to catch up. You finished the work while the others were still uncapping their pens.
Outside school, life was harder, though you did not know that yet. You had nothing to measure it against. You had not yet understood that other children were growing up with support, resources and encouragement that were simply absent from your own house. School and the climbing gym were the places where you feelt good and confident.
Your future was neatly planned out. Finish school, study medicine, graduate at twenty-four and start a family of your own by thirty. A room you had furnished in your head, every piece chosen and set in its place. It gave you what you needed, orientation, calm, discipline and drive.
Then, at seventeen, a few minor symptoms turned into a long diagnostic journey. Doctors pushed long needles into you the way you would push strawberries and slices of banana onto a skewer. It ended with a sentence. You have a genetic mutation so rare it has only been recorded fifteen times in the world. We cannot tell you how it will progress. We cannot tell you what it will cost you.
Weeks before the medical school entrance exam, you almost died. You failed the exam. In the months that followed, everything came crashing in and you were left standing in the rubble of who you had been. The doors that had stood open to you slammed shut.
When the doors slam all at once, you feel it. The closing is loud and you know exactly what has been taken. Doors close like that only rarely. Most of the time they close one at a time, quietly. And sometimes you are also the one closing them. Every choice you make shuts something. This is called path dependency.
Path dependency
Stand at any moment of your life and there are a set of branches fanning out from the present depicting possible futures. The things you could do next, the cities to move to, the people to meet and the work to pursue - the whole shape of the next ten, thirty, fifty years. You only are able to go after one path at a time and the instant you do, the rest close. The etymology of "decision" shows this, as it derives from the Latin verb decidere, which literally means "to cut off."
Cutting the other branches off is only half of what a decision does. The branch you keep does the other half. It becomes the ground the next decision stands on. Every fork that opens in front of you later is there only because of the one you already took. Choices do not sit side by side in time. They stand on each other. A small turn near the start bends the whole line of a life away from where it would have run (Arthur, 1989).
You move to London for the job. From that day every friend you make is a London friend, every chance meeting a London meeting, the person you fall in love with is someone who happened to be in London that year. The Lisbon life was never lived. You cannot even mourn it, because you never found out what was in it.
Because a life is built this way, you cannot read it from where it currently stands. The present holds the result and hides the cause. What explains an outcome is the route, the steps that led there and then stopped showing on the surface. Two people can reach the very same spot, with the very same options in front of them and still stand at the mouths of different futures, because they walked different routes to get there.
Two routes can be made of the very same steps and still not be the same route. What separates them is order (Pierson, 2000). The same two events in the other order make a different person. The same wins and the same losses, reshuffled, do not sum back to the same place. Replay the whole sequence from the start and you would not arrive here again (Gould, 1989).
Path dependency also illustrates the difference between linearity and complexity. In a linear system the parts do not touch each other. The same inputs give the same output every time and you can read the ending off the starting conditions. A life is not linear. It is a complex system, where every part bends every other part, where the person you met at twenty changes the job you take at thirty, where the order in which things reach you decides what they do to you (Lorenz, 1963). In a system like that the present can never hold the whole story, because the story was written by the way unrelated things happened to collide along the way.
The forks you did not notice
This has already happened to you, many times over. The strange thing is how few of those moments felt like decisions while you were inside them.
We brace for the big choices. We expect the fork to announce itself, to arrive with weight and a sense of occasion. The forks that set the shape of a life almost never do. Most often they look like a normal Tuesday, and while living this normal Tuesday we do not feel the gravity of the choices we make.
You were born in a particular country, to particular people, into a particular language and a particular amount of money. You decided none of it. And that one non-decision shaped the range of lives open to you more than every deliberate choice since. The passport, the mother tongue, the schools within reach, the things you believed about the world before you were old enough to test them. Your life began already deep inside a tree somebody else had been walking for decades.
Then, at eighteen or nineteen, you chose a direction. You chose it with almost no information, as a person who barely existed yet, on the strength of a teacher you liked or a salary you had heard about or a parent's quiet Or not so quiet. hope. And then the choice began to defend itself.
You got good at the thing. Getting good at it made staying reasonable and leaving expensive. Ten years on, the direction you picked at nineteen is most of what you now are. The competence you built is the same competence that keeps the door behind you shut. Each year you do it well makes the next year of doing it a little more certain and every other path a little fainter. An economist would call this increasing returns. It ends in lock-in. The early choice keeps paying you to repeat it, until repeating it is most of who you are.
And the person. You can probably name the afternoon. A friend cancelled, so you went alone. Missed the first train and had to take the next one. Leading you to arrive there at the exacte same time as the person you then built a life with. All starting at this afternoon. And with that person came everything downstream, the children and the city you settled in and the version of yourself they drew out of you. The whole load-bearing structure of an adult life, resting on an afternoon you at first had no way of knowing to pay attention to.
The forks that are yours
The forks behind you were to some degree chosen not under your agency. But the forks ahead are a different matter, as some of them are yours, genuinely yours.
We mostly decide by asking what a choice will give us, the better salary, the shorter commute or the title that sounds good, said out loud. We weigh the fruit on the nearest branch. But the fruit might be the smallest part of what a choice does. The branch you step onto sets the shape of every branch that comes after it, so an option that pays well and quietly but at the same time closes forty other branches is worse than one that pays less and keeps optionality. The payoff sits on the branch, but the more important part might me all the fruits on future branches that you lose access to.
Going left once does not have to mean you can't go left in the future. Many decisions are reversible and the cost of reversing them is sometimes moderate. A haircut only needs time. Moving jobs, the city or the flat will cost more, but you can redecide. A few are not like that. A child, a debt secured against everything you own or field you have given fifteen years to. With these the some options close for good.
Understanding this part of path dependency might create the feeling of wanting to keep every branch open. If every decision kills a thousand possibilities, the careful move might look like deciding as little as possible, keeping the tree wide and waiting. Holding every option open is itself a decision and there is also a price for not deciding or deciding too late. So you close worlds either way. What stays yours is whether you close them with your eyes open or shut. The worlds you closed with your eyes open are most often not regrets. Something closly linked to what Nietzsches (1888) calls amor fati, the love of your fate. A world you give up knowingly is the price of the one you keep.
It is yours
Go back to the seventeen-year-old from the beginning, standing in the rubble of his identity. The white coat, the graduation at twenty-four, the room he had furnished in his head with every piece set in its place. He could only count what the closing had taken, but what he could not see, was that rubble is also building material. Every fork he has reached since was reachable only from that valley. Oblivious to the full workings of path dependency, he was at an unnecessary nihilistic place, but you, now having opened the Pandora's box of path dependency full, don't have to.
True, every decision is the death of a thousand possibilities, but wherever you might stand, there are thousands of possibilities fanning out in front of you.
References
Arthur, W. B. (1989). Competing technologies, increasing returns, and lock-in by historical events. The Economic Journal, 99(394), 116–131.
David, P. A. (1985). Clio and the economics of QWERTY. The American Economic Review, 75(2), 332–337.
Gould, S. J. (1989). Wonderful life: The Burgess Shale and the nature of history. W. W. Norton.
Lorenz, E. N. (1963). Deterministic nonperiodic flow. Journal of the Atmospheric Sciences, 20(2), 130–141.
Nietzsche, F. (1888). Ecce Homo (W. Kaufmann, Trans.).
Pierson, P. (2000). Increasing returns, path dependence, and the study of politics. American Political Science Review, 94(2), 251–267.