Objection: You are your brain. When the brain dies, you die. Period.
Reply: This is not reductionistic enough. Experience is not an object called brain. Experience is probably found in thalamo-cortical Gamma oscillations which are present during both dreams and waking life. And by probably, I mean that there is considerable evidence* (Llinas & Pare 1991, Eckhorn et al. 1988, Engel et al. 1990, 1991a, 1991b, Gray et al. 1989, 1990, 1992, Gray & Singer 1989, Stryker 1989, Llinas & Ribary 1993). The wave sweeps the brain from front to back, 40 times per second. The precept which you are at any given moment is the shape formed by synched neuronal circuits.
(*Some still suggest that this does not solve the binding problem. See Steven Lehar who, in short, proposes that the synchrony observed between cortical neurons is not a signal in its own right communicated from cell to cell but that it is a manifestation of a larger standing wave pattern that spans the cortical region and that the structure of the standing wave encodes certain aspects of the structure of the perceived object or grouping percept. But it is possible that this concern is merely a bias against time delays. The cause of this bias may be from holding on to a presentist ontology. The computation can be stretched in spacetime and may still be “glued” for the act of phenomenal binding by its ‘mere’ four-dimensional geometry.)
If the thalamus is damaged even a little bit, the wave stops, conscious awareness does not form, and “the patient” slips into profound coma. –You are not the patient experiencing a profound coma because a profound coma cannot be experienced. You are all precepts, wherever they exist as conscious computations, and can never realize that you are also others. There is only one universal wave-function. This contains approximate factors that we think of as objects with persistent identities including the object type which is “shape formed by synched neuronal circuits.”
If we change the definition of “you” to not be mere experiences, such as the synched ventral/dorsal pathways that produce the sight of beautiful green eyes in a lovely girl, or thalamic vortex resonating with dopaminergic pathways which produce the qualia particles of bliss in a luxurious dinner, but instead define “you” as a body that will be somewhat similar tomorrow and which will reliably hold “you” in memory, then that body is toast. Those memories are toast. I am not offering snake-oil repellent against entropy here. *Edit: I was. The singularity already happened and all you have to do is to realize this knowledge with your rational thought so that the magic is revealed. Here, you can choose to experience the deathless, which does not perceive entropy.
Not even quantum immortality can save you, if that is how you is defined. You will become quite computationally defunct, whether by neurofibrillary tangles or whatever else. If you manage to transition into a sufficiently degenerate state, your experiences can become physically indistinguishable from many “other” experiences across the universe. Spatiotemporal separation does not matter; only the shape of the computation does. When we are in very low-awareness sleep, our uniqueness dies and yet experience doesn’t. Those dim states of almost-nothingness, lacking a sense of self, are dips into the well of greater unification where the net amount of minds in that identical configuration are larger than compared to the highly unique experiences we go through in everyday waking life. It wouldn’t be a far-fetched hypothesis to suggest it is also possible to experience this computational simplicity through intensive meditation practice, drugs, or being barely conscious i.e. some processes in young children, Alzheimer’s, near death, dolphins?, chimps?, corvids?, etc.
Note that this is compatible with the multiple drafts model. There is no anatomical location where it all comes together and is presented to a homunculus.
They suppose that the transduction by sense organs of light and sound and odor and so forth into an unconscious neural code must be followed (somewhere in the brain) by a second transduction into some other “medium”, the medium of consciousness (e.g., Mangan, 1993).
But there is no transformation to another medium of soul stuff. It is then the case that there is no privileged reference frame for the enormous flood of experiences that exist across the universe.
Objection: This will demotivate people from engaging important issues such as ending aging or cryonics.
Reply: Note that this objection is normative. It is inevitable that the truth can be made dirty in the act of converting it into petroleum for cryocrastination and the pro-aging trance; this human behavior is not relevant to the question of whether physicalism implies immortality.
Having said that, it is my contention that being aware of immortality is a powerful antidote to nihilism. For better or for worse, you have skin in this game for the long run and cannot escape. If people were rational, they would feel motivated to work on Strategies for Engineered Negligible Senescence with even more fervor because the terminal punishment for not doing so isn’t restful non-existence (which some people hardly find punishing). And not signing up for cryonics is the equivalent of not pressing save and then letting someone else pick which game you will be playing next.
Going on the basic anthropic assumption that we’re trying to do a sum over conditional probabilities while eliminating Death events to get your anticipated future, then depending on to what degree causal continuity is required for personal identity, once someone’s measure gets small enough, you might be able to simulate them and then insert a rescue experience for almost all of their subjective conditional probability. The trouble is if you die via a route that degrades the detail and complexity of your subjective experience before it gets small enough to be rescued, in which case you merge into a lot of other people with dying experiences indistinguishable from yours and only get rescued as a group. –Eliezer Yudkowsky
This was part of a comment in a post discussing… quantum torment, of all things.