The self arises, and we act. Occasionally, we can examine the emotive urge before enacting the impulse, but when we explore where the urge came from, the self recedes and dissipates, leaving us confounded.
The urge to define (capture) “the self” is scientific. The compulsion to examine is the same urge that euthanizes butterflies and pins them to a board for cataloging.
But of course, this captured “self” cannot contain the whole self, the leftover self is still studying and reacting to context, flitting away from the collection of facts pinned down.