The form is subject to the law (a set of agreed restrictions), which determines its shape and reactions.
To identify with the form (the shape) is to become bound to its laws.
In being "you," you bind yourself to consistency: a form of "you" with a set of laws.

Yet the world is a process of change, and to become the form is to calcify the self and cease being aware of the world, lest it disrupts your formation.