Enterprise’s Dr. Phlox is definitely one of the show’s more interesting characters. One of our favorite episodes in which Phlox figures prominently is “Dear Doctor”. In the episode, because postcard printing doesn’t seem to exist in Captain Archer’s time, Phlox is dictating a letter to a colleague on his home world and the letter is used as a narrative throughout the episode.
The crew encounters a world with two intelligent species, one of whom is dependent upon the other, which is dying of because of a genetic virus.
Phlox determines that the dependent species is undergoing an awakening of sorts and could, eventually, dominate the planet if they weren’t completely dominated by the other species.
Phlox developed a cure for the disease that is killing off the dominate species, but doesn’t feel that it would be morally correct to administer the cure. He expresses the opinion that they should let nature decide which species will survive.
His discussion with Captain Archer about the subject is the first hint of a mention of the Prime Directive in the Star Trek timeline.
