Consider an overall "knowledge graph"

[KnowledgeGarden]

This would be a full-scale graph, perhaps with D3.
UX envisaged:

• Top of page is typeahead box to select a topic.

• Selection paints a graph around that topic - likely by ajax, perhaps radius = 2 by default

• Clicking a leaf node provokes an ajax fetch to go another radius from that node, if any

• Double-clicking a node opens the topic page (perhaps in a sidebar?)

Note: this references D3 - it may be that we will have to replace vis.js with D3 in the topic graphs