My understanding of differentiation of self after listening to Murray Bowen and reading the materials is that each person emerges from the multi-generational family organism with a certain amount of undifferentiation (or fusion) that needs to be handled using various mechanisms such as distance, conflict, over/under-functioning, and/or projection to the next generation. The more self that one has, the less intense these mechanisms will appear given a certain level of anxiety. With that same level of anxiety, a person with less self than the previous person, the mechanisms will be more intense.