As the name implies, finds the shortest path between two Wikipedia pages.
Whatis.com defines serendipity in part as:
In general, serendipity is the act of finding something valuable or delightful when you are not looking for it. In information technology, serendipity often plays a part in the recognition of a new product need or in solving a design problem. Web surfing can be an occasion for serendipity since you sometimes come across a valuable or interesting site when you are looking for something else.
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Serendipity requires exposure to things you aren’t looking for, search engines excel at that, but their results are so noisy that serendipity is a rare occurrence.
Six Degrees of Wikipedia may have a different result.
First and foremost, humans created the links, for reasons unknown, that form the six degrees of separation. The resulting six degrees is a snapshot of human input from dozens, if not hundreds, of human actors. All of who had an unknown motivation.
Second, the limitation to six degrees results in a graph and nodes that can be absorbed in a glance.
Compare to the “I can make big and dense graphs” so typical in the “analysis” of social media results. (Hint: If any US government agency is asking, “The Russians did it.” is the correct response. Gin up supporting data on your own.)
Six degrees between topics would make a fascinating way to explore a topic map, especially one that merged topics from different domains. Randomly select labels to appear along side those more familiar to a user. Provoke serendipity!