What is consciousness? What is a self? How did it come to be? What types of selves exist?
If you like thinking about these questions, you will probably enjoy The Ego Tunnel — an excellent exploration of the philosophy and recent science of consciousness and the nature of the self. Personally, I find these issues fascinating, but also so complicated that periodic revisitations are required to integrate the associated facts and arguments into one’s worldview.
Metzinger argues for the self as a process, as something that comes together from the combined action of brain areas activated at similar times. Although it is a radical idea, I already agreed with this, but the uninitiated might find it startling. If you open up the brain, there is nobody home, so where are “you”? Most of our brain's processes are so automatic that we do not have access to how our perceptions are formed. Simply put, you can’t. If you could, the perception itself would crumble. For example, if you are holding a red apple, you have a sense of its weight, but you do not have first-person access to the processes that enabled you have to that sense of its weight. On a related note, the redness of the apple isn’t "out there" in the world, but a creation of your brain being affected by electronic impulses sent from your eyes, which are processing different wavelengths of electromagnetic radiation. Many sciencey people know this last point, but I would argue that while such facts can be understood on some level, they are incomprehensible from a subjective standpoint.
Metzinger provides a good introduction and overview of his model, and how it fits with neuroscientific findings. There are decent chapters on lucid dreams and out-of-body experiences, and some interesting interviews at the end of a few chapters — my favourite being the one with the theoretical artificial advanced self we create in the future. The Ego Tunnel raises some important ethical issues surrounding the creation of artificial selves and Metzinger cogently proposes a new field of ethics — consciousness ethics — to deal with it. For example, if we can create conscious selves, it is likely our initial versions would be greatly diminished in capacity (compared both to us and to future versions of themselves). Would such diminished creations, which we’ll be experimenting upon, be similar to a retarded human baby, or something more like a cat, or something entirely different? Complicated issues, indeed!
I found the entire work quite enjoyable and, if pressed, my only criticism would be to say I found the middle third ‘only’ interesting as opposed to first and last thirds which were very interesting. The self and consciousness are not what they seem. If you are curious to investigate further, The Ego Tunnel is a decent place to start.
I experienced the work as an audiobook, which was narrated at the perfect pace to challenge my ability to understand the content. The Ego Tunnel is supposedly a more accessible and condensed version of Metzinger’s Being No One, but since I only have that behemoth on my shelf and haven’t read it, I can only say that is likely true based on the table of contents and length alone.
I highly recommend this work (and hope this will be a useful primer for Being No One).