The notion of a conscious model of oneself as an individual entity actively trying to establish epistemic relations to the world and to oneself, I think, comes very close to what we traditionally mean by notions like "subjectivity".

As a philosopher, you define constraints for any good theory explaining what you are interested in, then you go out and search for help in other disciplines.

What many people don't see is that there are abundant examples of phenomenal opacity: It is one of the most interesting features of the human conscious model of reality that, first, it can contain elements that are not experienced as mind-independent, as unequivocally real, as immediately given, and second, that there is a "gradient of realness" in which one and the same content can be experienced transparently or in an opaque fashion.

The conscious experience of being a subject arises when a single organism learns to enslave itself.

Subjective time flows forward, the phenomenal self is embedded into this flow, an inner history unfolds. That it is why it is not a bubble, but a tunnel: There is movement in time.

One of the interesting characteristics of the Ego Tunnel is that it creates (as Finnish philosopher Antti Revonsuo called it) a robust "out-of-the brain experience", a highly realistic experience of not operating on internal models, but of effortlessly being in direct and immediate contact with the external world - and oneself.

When you are simply observing your breath, you are perceiving an automatically unfolding process in your body. By contrast, when you are observing your wandering mind, you are also experiencing the spontaneous activity of a process in your body.