Path Dependence

The likelihood that something will continue to be done the same way it was done from the outset. This can be readily observed in technology. For instance, the width of train rails is the width of a horse pulled cart (or “two horses asses”) and led to the width of rockets on the space shuttle being set to a size not based on what is optimal, but based on what can be transported via train.

See also:

  • Lindy Effect

    A theory that states, the future of an idea or technology is proportional to how old it currently is so that every additional period results in longer life expectency.

  • Update Your Priors

    An expression for Bayesian thinking where you think in ranges of outcomes based on prior information. When new information arrives, to get a more accurate range of solutions you ‘update your priors’.

  • Outdated Scientific Studies Can Perpetuate for Years

    Scientific research can sometimes suffer from a form of path dependence where a single study can be cited repeatedly for many years even when it is found out to be incorrect. For example, in 2015 a literature review found that 900 peer-reviewed studies used a cell line derived from a breast cancer patient in 1976 that was found to actually be skin cancer. For eight years (and maybe more) studies kept citing it even though it was incorrect.

  • The Default Strategy for Dependencies Should Be to Not Add More

    Adding new dependencies to a codebase is a net positive until it’s not. The added leverage of picking up an off-the-shelf solution eventually gives way to dependency hell—fixing breaking changes, incompatibilities between things, security issues, and so on.

  • Justificationism Secures Ideas Against Change

    One way to answer “how do we know…?” is to justify one’s belief by reference to an authoritative source or cornerstone of knowledge. This is, in effect, saying “by what authority do we claim…?” which seeks endorsement in order to have certainty. Justificationism as a theory of knowledge therefore resists change (or at least delays in a form of path dependence).