# Module assembly and evolution are two ends of a spectrum It feels like there are actually two different things that a linkage in the tech tree can signify: 1. that two ideas, when combined led to an idea that doesn’t *contain* either of them. For example the model T line doesn’t actually contain the meat processing line. But it does contain pieces of it. * Something about an idea becoming *embedded* in a technology * There’s also something to the term adapted. 2. That two ideas are actually contained in the new thing like how a steam engine depends both on a regulator and a sun-and-moon gear. Maybe there is only one way that they’re actually combined but you may need to decompose and then adapt *pieces* of a precursor heuretic. This may suggest that whenever you see something that looks like evolution it’s a sign that you haven’t sufficiently decomposed the heuretic enough to see which pieces were incorporated into the new thing. [[What do genes look like for technology?]] Let’s think about muskets ‘evolving’ into rifles - we could modularize the musket into the firing mechanism, the bullet, and the barrel. The difference between a musket and a rifle is that the rifle barrel has rifling. You could accurately say rifling + musket system -> rifle system but a rifle obviously doesn’t have a musket as a module. More accurately you would say musket = {firing mechanism, barrel} + rifling -> rifle system = {firing mechanism, barrel, rifling} This seems a little bit naval-gaze-y but it is meant to illustrate the important point that “evolution” always involves some amount of addition, subtraction, or substitution. This ties in to [[And Suddenly the Inventor Appeared]] ### Related * Is this saying the same thing as [[The tech tree is trying to both capture the current state of hierarchical heuretics and the recombination of heuretics over time]]? * [[Modularization enables pieces to be used in many different technologies]] <!-- #evergreen --> [Web URL for this note](http://notes.benjaminreinhardt.com/Module+assembly+and+evolution+are+two+ends+of+a+spectrum) [Comment on this note](http://via.hypothes.is/http://notes.benjaminreinhardt.com/Module+assembly+and+evolution+are+two+ends+of+a+spectrum)