The light of the Tzaddik Ha'emet/true tzadiq himself has been revealed to us -- it is our Rabbi [Nachman] z"l. We need to cling only to him and not seek in other places, for he is a new way, like Rashbi and the Arizal and the Baal Shem Tov in his uniqueness. And after him there shall be no more new [ways/revelations] until our righteous Mashiach.
And [just] like it is hard [to understand], why Rashbi had to come to the world -- was it not enough that Moshe Rabeinu, alav hashalom, [came], who was already etc.? [But] our Rabbi z"l already said in Chayei Moharan: Only before the Tzaddik Ha'emet is in the world, can people draw close to the Blessed Lord (i.e. via the previous ways), but when the Tzaddik Ha'emet has already been [here], then it is impossible to draw close to the Blessed Lord without his way and advices, because there are now new sicknesses of the soul (now in the world), such that (each person) needs his healings (of this Tzaddik).