Path-dependent: Difference between revisions

}}{{d|Path-dependent|/pɑːθ-dɪˈpɛndənt/|adj|}}{{c|newsletter draft}}

Of a circumstance, that its coming about can only be explained by the sequence of events and contributing factors that lead to it; that it cannot be justified or explained by reference only to existing conditions.  

The classic case is, of course, evolution by natural selection: re-run the tape from the beginning and you would ''not'' get the same result.

 

 

 

Removing it is not a simple appeal to dispassionate logic, or the prevailing cultural mores, but requires more path-dependence. The longer it has been around, generally, the more deeply will it be embedded in the cultural, political or even biological layers of humanity, and the more concerted, insistent and patient will be the effort to change it need to be. 

 

 

 

 

 

 

[[Backtesting]] is a preposterous idea.

 

By the lights of history, the market’s course is now fixed. The data is dead. Inert. But when you are ''there'', in the moment, it is ''not''. It reacts to you, and you react to it. It is dynamic. Symbiotic. Contingent. Alive. 

 

A trading strategy derived from the fossil record of data that was once alive, but is now not, is similarly inert. It is cannot ride, or get swamped by, the symbiosis between market and participant. 

 

This is true of any [[algorithm]] that depends on data. Data is history. A photograph. It is good for answering questions to which there already is an answer. (Don’t scoff at this: many good questions are things for which there is already an answer; just one we don’t personally know. Hence: the value of Google. The value of a ''library''.)

 

 

 

By looking at a unitary history (that we made up), in hindsight we miss the contingency from which it was fashioned. Once it is laid down, it looks inevitable. It looks pre-ordained. This is a curiously ''religious'' idea.

 

 

The temptation, when we look at such a concrete past, is to see each of the points behind us on that timeline as having determined the remaining history to the present. The extrapolation is that they must determine the future, too. The further back in time a point is, the more momentous it has been in determining our path to here. This seems intuitive: the decisions I made ''yesterday'' had little bearing on where I am today: I was already here. The die was long since cast.

 

 

 

We have, and our ancestors had, the ongoing ability to change things daily. ''Everyone'' makes bad decisions. The key is not to be ''defined'' by them. Everyone makes ''good'' decisions, too. Keep the good decisions, do what you can to subsequently correct for the bad ones.

 

 

You can’t undo the decisions of the past, whether made by you or about you, or by your ancestors or about them. ''You can make different decisions now''.

 

 

 

The “tight” version is a form of [[data modernism]]. Every branch of the world ash of destiny, every atomic reaction, every operating impulse of the universe is, in principle, calculable and that we have not yet done so is down to our own feeble calculating machines. Many serious intellectuals believe this. If it is true, then everything in the future is inevitable, immutable, and there’s nothing to be gained from grousing about it.

 

The “loose” version still says there are better and worse ways of interacting with the world, they can be — ''must'' be — deduced objectively, that is, without reference to any person’s subjective standpoint regardless of how marginalised, and this is precisely what the social institutions [[standpoint]] theory so criticises are there to so. So, there's nothing to be gained from grousing about it.

 

 

Articulation of history is necessarily a simplification, and model, a boiling down of an infinity of information into a single digestible [[narrative]]. It necessarily misses things: relegates things; deems things extraneous. But what the dominant narrative things is important and what the community thinks is important are not the same. In the same way that informal systems and interactions, unseen by the executive actors, are critical to the good order and smooth operation of the state, or a business, so are informal, unobserved, and deprioritised interactions fundamental to history. Models ''lie''.

 

So not only is “the past” — as we articulate it — inert and immutable, it’s not even ''true''. We can, and do, adjust it by changing our account of it. History is written by the winners — but it is a long game and just who is the winner is prone to change. Those who dominate the narrative from time to time decide who the winners are. This is the Orwellian concept: write and re-write and erase our history, whilst insisting on its utter continuity. It may be so that the external history of the universe is immutable — but we have no access to that. We wouldn’t recognise it even if we had it. We can only tell ourselves stories, and they have internal meaning, but no transcendent one.