To manipulate language is to manipulate one's mask, and therefore is the prime method of manipulating others. And Browning's characters are above all interested in manipulating the responses of others and controlling them so that they take the speaker's mask at face value. Yet if the speaker talks long enough, like the rest of us, his manipulative control begins to break down; and he reveals not the reality behind the mask but the mask behind the mask. It is almost as if Browning conceived of the personality as an infinite regression of masks, and perhaps he did.
However, the other side of the coin is equally important. It is the mask of language, and language as mask, that not only facilitates but permits interaction. Manipulation of one's self and others in the furtherance of certain life-essential interests is the way we live, and what makes it possible for us to live....To present publicly one's self-conception, the mask behind the mask, is on the one hand to force one's attitudes on others and on the other to expose oneself to unnecessary challenges. The full development of subtle and profound concepts requires protection. Without that protection either one's confidence is shattered or one becomes engaged in contention, and the worst kind of contention, sincere contention....To be sincerely contentious is to lose one's insights in sincerity, for the development of insights requires that one uncover, in secrecy, one's own insincerity, something impossible to do if one is busy defending them. The defense of a position hypostasizes it, reifies it, commits one to it, and ultimately leaves one stuck with it.
--Morse Peckham, "Personality and the Mask of Knowledge" in Victorian Revolutionaries