SAN DIEGO — The Republican Party keeps announcing its new modernity, declaring its new inclusiveness, swearing that it has changed and then showing that it hasn’t.

Witness Rand Paul, who is supposed to be one of its fresher, unconventional faces.

He spoke at a dinner here on Saturday, in a blazer and khakis instead of a suit, and once again presented himself as a Republican unusually in touch with the sensibilities of younger voters, especially concerned about the welfare of minorities and uniquely positioned to expand the party’s reach.

It was a refreshing pitch — until a medieval metaphor revealed an antiquated mind-set.

He was describing people’s need to feel that their personal information in cyberspace is as safe from indiscriminate government snooping as the documents in their dwellings have long been, and he mentioned the adage that “a man’s house is his castle.”

Then he updated it: “Now we would say a man or a wife’s home is their castle.”

A man or a wife’s?

Aiming for a less sexist, more sensitive vocabulary, he came up with a more sexist, less sensitive one, casting women as auxiliaries of men.