Map is not the territory

Coined by philosopher Alfred Korzybski. “The map is not the territory” is a reminder that it is impossible to perfectly model a system (see:

Even if we wanted to model everything, we couldn’t. Gödel’s Incompleteness Theorems say that every non-trivial (interesting) formal system is either incomplete or inconsistent. Extended, this means it’s impossible to know everything about a system that’s worth knowing things about. We must come to accept uncertainty.

Indeed, science is revealing uncertainty at the fundamental levels of physics.

A perfect model of a system would be the system itself. According to Ashby’s Law of Requisite Variety, a perfect regulator must have at least as many distinguishable states as the phenomenon it is intended to regulate. In other words, to build a perfectly accurate model of a system, the model needs to be at least as complex as the system itself. Likely, it will be more complex.

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What is more valuable than making detailed models is making models that are useful. Useful models include the a decent amount of relevant information so we can make a decision better than without the model. You can consider a time vs. complexity payoff.

A common problem when making useful models is knowing when to stop. Adding too much has a double penalty of both increasing mental capacity required for reasoning while making it harder to find the useful bits.

TODO: Expand on techniques that help you decide when to stop

Making a perfect investment decision would require modelling at least the entire galaxy.

Making a perfect software model of a cat would require making a cat, down to the subatomic particles.

Making a useful model of a cat would depend on the context of what you’re trying to achieve. It’s possible to make a very useful model of a cat if you’re trying to predict cat health.

Making model of a system that is too complicated, or modelling parts of a system that aren’t relevant to your current inquiry is useless and often a waste of time.