contribution (or not) guidelines in README.md?

Hi Merlin! Thanks for putting this up on Github, it's an interesting document.

Reading this document sparks lots of ideas, and in a McLuhanist way, seeing it in the context of a Github page makes me feel like I am encouraged to share those thoughts via pull request. But… am I? It's not totally clear whether this is intended to cultivate a community consensus of wisdom or whether this is exclusively Merlin's wisdom document. It might be nice to have a brief paragraph in the README explaining something like "If you like it and have more ideas feel free to make your own fork and make your own wisdom document" or "pull requests for [purposes] are welcome, but if you want to change [some core thing] it might be better to keep your own fork" (or even just "please don't").

(I suggest this not because I think my own ideas are particularly pressing, no promises that I'd ever even send a PR, but rather it might be very annoying to have not set these expectations before this hits the front page of some website that draws a few tens of thousands of potential PR-senders who may not have this restraint.)

Start by reading README.md and the two comments in this issue to understand the repository's intended contribution model. Confirm the maintainer's preferred expectations, then document the agreed guidance in README.md. Done means the README clearly explains whether forks, pull requests, or both are welcome and for what purposes.