# The tech tree is a scaffolding inside the knowledge frontier If the [[Knowledge frontier]] is the surface of a high dimensional blob, then you can imagine the tech tree as the scaffolding holding the whole thing from the inside. Any time that you add a new leaf to the [[§Tech Tree Model of Heuretics]] you’re expanding the edge of the knowledge frontier. This realization came from the question of “what does one technology superseding another actually entail?” It means that the technology has a larger impact. If the environment is fixed, larger impact means that it is higher than another on the relevant dimensions for that environment. ([[A heuretic’s impact is not endogenous to the technology but depends on the environment]]) *That* in turns that we need to be looking at innovations in a massively multidimensional way. The *same* way that we look at the knowledge frontier. This model gives a new way of looking at [[§Type I and Type II Progress]] because Type I progress starts to look like progress endogenous to the tech tree, while Type II progress looks like expanding into a new environment. 🤔