Remember - sanity is a LEGAL term, not a psychological one... has to do with going along with the majority. So if you heard voices in the Middle Ages, you were blessed, but now, you're insane.

While there is a term "sanity" defined in legal processes it has nothing to do with the actual condition or lack thereof except to rely on a psychological capability grounded in knowing the difference between good and evil, roughly. Legally, of course, it has been and endless chatterbox full of maybes and speculations.

But I don't believe it is correct to say there is no measure or metric that can approximate the opriginal, pre-legalistic meaning of the word (healthy in mind).

Even though there are multipple variables involved, I think it is a useful term for communicating the relative degree of strength and clarity of mind in an individual, in a sort of composite sense.

A