The topic is self-observation. And it's "defined" by limitations. And those limitations, while being created - and an illusion - allow access to what is unlimited. So, here we're going with limitations. The beautiful thing about the unlimited and infinite is that is contains limits and finite aspects.
Practice self-observation uncritically. Do not become identified with what you observe. Try to separate psychologically from all negative thoughts, states, and feelings. Release anxiety, let personality be passive, and observe, observe, observe.
That can lead to mushin, which is defined in Gurdjieff's language as "self-remembering."
I was quite familiar with mushin long before I began training martial arts. Firstly, I was a kid. Childhood can be a great place to explore mushin. As I got older, and as a musician, I spent countless hours as an improvisational jazz musician. Jazz can be an ocean of mushin.
It appears that we need some kind of form - some set of limitations - in which to practice, and use as a gateway to mushin. In this topic I'm focusing on the form. The form can be an illusion. The form is created. It's simply a created set of limitations in which to operate.
Within those limitations, there are no limitations. That's the infinite within the finite - as well as the finite within the infinite. No-mind is entered and exited through mind. And mind is entered and exited through no-mind. Illusion is entered and exited through the real. And the real is entered and exited through illusion. Movement is entered and exited through stillness. And stillness is entered and exited through movement. And entering is entered and exited through exiting. And exiting is entered and exited through entering.
They are the same.