adjectives - "It is not well" or "it is not good"?

Watching an old Dr. Who episode, one character said to another,

"Highness, it is not well to think of the past, there is still the future to make."
_{("The Ribos Operation", 1978)}

To my ear, this sounds wrong and should have been,

"Highness, it is not good to think of the past, there is still the future to make."

Unfortunately, other than the way it sounds, I cannot determine the applicable grammar rules to know if I am correct.