#mental-model
# [[Epistemic status]]
#shower-thought #to-digest
# Changelog
```dataview
TABLE WITHOUT ID file.mtime AS "Last Modified" FROM [[#]]
SORT file.mtime DESC
LIMIT 3
```
# Related
- [[Eric Ries - The Lean Startup|The Lean Startup]]
# TODO
> [!TODO] TODO
# Lean
In business it's often recommended to follow a lean process, i.e. you see a problem, you make sure the problem is really faced by other humans before building anything.
In https://github.com/karpathy/nn-zero-to-hero Karpathy implements a neural network in a lean fashion, only the most important value brought by artificial neural nets, that is [[en.wikipedia.org - Chain Rule - Wikipedia|chain rule]], [[Back-propagation]], [[Automatic differentiation|autodiff]].
Lean is a mental model that emphasises investing the minimum effort to get the maximum value.
## Example
- **Lean problem solving**: Solving Leetcode problems: solve the problem with your human algorithm (which for some reason is usually the retarded inefficient algorithm, are we intuitively inefficient problem solvers?) - then implement this human algorithm in machine algorithm (code) - if it work think how to make it more efficient.
- **Lean learning**: https://github.com/karpathy/nn-zero-to-hero -> he implements neural network from scratch, computing derivatives by hand if necessary, each layers of knowledge being examined
- **Lean startup**: minimum effort that helps the problem, human work if necessary even if you can code it (evaluate [[Philosophy/Rationality/Opportunity cost|opportunity cost]])
# External links