The Morphy number is a measure of how closely a chess player is connected to Paul Morphy (1837–1884) by way of playing chess games. It's analogous to the Erdős Number for mathematicians.
People who played a chess game with Morphy have a Morphy number of 1. Players who did not play Morphy but played someone with a Morphy number of 1 have a Morphy number of 2. People who played someone with a Morphy number of n have a Morphy number of n+1.
In my case, in the early 1980s, I played Jonathan Penrose in a simultaneous exhibition, the cosmic significance of which was unknown to me at the time. Penrose is one of the few living MN3 players, having played Savielly Tartakower in 1950, who played James Mortimer in 1907, who played Paul Morphy himself "hundreds of times" from 1853. So that gives me MN4. A bit lucky: if I hadn't got that connection to Penrose, I might be hard-pressed to find my number.
Jonathan’s brother is the celebrated physicist, Roger Penrose.
So how does someone go about finding their Morphy number more systematically? Has anyone data-mined chess games databases from this perspective? Have any results been published? What are the paths implied in the Wikipedia article linked above from the MN1 to MN2 to ... to MN5 players listed there? And what's the expected MN for an active player today?
Has anyone else here managed to figure out their MN?