This is a brilliant idea! And it’s great to hear that SkepticMystic and Emile are considering something like it.
I like the way CmapTools generates a text outline of the concept map. In that program, if the concept map has any circularity, the text outline can be expanded “infinitely”, but I think there would be a workable way to encode the concept map in a Markdown file. For example, if we say that * indicates a ‘card’ and - indicates a link, the Markdown text for @callan’s concept map could be something like the following:
* [[Co-design]]
- is
* A form of participatory design
- with roots in
* [[Scandinavian design]]
- with roots in
* Corporate and industrial design
- that
* Shares power
- similar to
* [[Action research]]
* Involves non-designers in the design process
- can be
* Can be difficult for government to implement
- because
* Shares power
The parser would either need to recognize that lines with the same text should be the same card (both occurrences of “Shares power” in this example), or else there could be a way for the parser to work with block references, so that the second occurrence of “Shares power” would be a block reference of the first.
So, the hierarchy would simply be a way of encoding the relationships between linked cards, and it would not enforce a tree structure. (Map position and so forth would need to be encoded separately.)
Ideally, with this kind of approach, one could edit text either in the underlying Markdown file or in the WYSIWYG whiteboard.
(Is this sufficiently in keeping with the original idea?)