I have ben thinking for some time about the utility of using an Erdős number type concept to help plot lineages.
If we take Freud's lineage of analysands, they could be numbered in generations.
There is , as with Erdos, a map of collaborations on papers to be drawn up.
There is also the potent power of institutions, Harvard, Oxford etc to be mapped. Dr Joe Kiff 20:04, 4 December 2006 (UTC)