Several weeks back, Facebook started suggesting a few people from a mailing list I've lurked on for years. I've never posted to this list. I get how they'd sugg

Several weeks back, Facebook started suggesting a few people from a mailing list I've lurked on for years. I've never posted to this list. I get how they'd suggest people with whom I've been in contact, even indirectly (e.g., via a mailing list); I want to know how they're suggesting people with whom I've never interacted in any fashion, that I happen to know (or at least know of).