To sustain intimacy for any length of time requires well-developed emotional and interpersonal awareness. Intimacy requires an ability to be both separate and together participants in an intimate relationship. Murray Bowen called this "self-differentiation". It results in a connection in which there is an emotional range involving both robust conflict, and intense loyalty.[7] Lacking the ability to differentiate oneself from the other is a form of symbiosis, a state that is different from intimacy, even if feelings of closeness are similar.