Something just hit me during my rewatch of "Lighthouse". How does Dogen know what a candidate is, but Richard doesn't? Since the beginning we were led to believe that Richard was second in command so to say. Could it be possible that Richard was never the advisor to Jacob, just a pawn in his little game of chess. Maybe Dogen is the true advisor or someone else that would know what a candidate is, such as Lennon or the new advisor-in-waiting Hurley.