They look at contracts (no privity, so that fails), copyrights (only protects monetary value, and only with things that actually are published, and also you can't copyright facts), assault/battery, libel/defamation (but this isn't just about harm to reputation), nuisance, etc. Technology is now enabling people to do things that existing remedies don't really address.
Finally, the come up with the right to be let alone. And the right of the "inviolate personality." The right to be left alone is both too broad (i.e., assault and murder aren't substantially privacy issues) and too narrow (i.e., doesn't cover passive surveillance violations) to accurately cover privacy. And "inviolate personality" is never really defined.
It's a good idea to think of this article in the context of 1890: there are economic and class developments under the surface-- so once again privacy is dependent on context.
Some pretty good thoughts, though, on what privacy is, as distinct from other rights.