Wiki Contributions


I have a friend on business in San Francisco with some free time Tuesday afternoon. Do any of you have a recommendation of how they should spend that time, outside of general suggestions as might be listed here?

"I believe that there is a biological variance in intelligence and insufficient information to allow for accurate qualitative analysis."

Your null hypothesis of each question assumes the difference, if present, will favour males; regardless of the theory's specifics, if you wish to gather fully rounded data on the opinions of your population, you must needs allow for that in the questions. If there's a theory that blue is finest on a Winter's day, and you wish to find out what people think of it, you must counter the inherent priming of the theory by including such options as, "Blue is finest on a Summer's day," and, "Blue is never the finest during day"; think of what the theory tries to answer. In these cases: the intersection of biology and intellectual variance between the sexes, and at what time is blue finest on Earth (you also may include, "Blue is finest on a Winter's day in Greenland, but in Madagascar finest on a Fall's day.")

Ah, then the purpose for my question is rendered moot. If it was an original coining, I wished to know the thought process that went into deciding, "Yes, I shall prime thusly."

For how long did you deliberate upon whether, or what did you think whilst deciding to go with 'Gallant' and 'Goofus'?

Intriguing, and thank you for the detailed reply. May I respond in the future should I have further queries?

I considered that, but the words seemed too different to result from a typo; I'm interested to learn the fact of the matter.

I've edited the grandparent to accommodate your interpretation.

What's the current thinking on how to prevent physiological decay over time (id est ageing)? Figure a way to recover the bits of DNA cleaved in mitosis?

We need to stop and (biologically) define life and death for a moment. A human can be cryogenically frozen before or after their brain shuts down; in either case, their metabolism will cease all function. This is typically a criterion of death. However if, when reanimated, the human carries on as they would from a wee kip, does this mean they have begun a new life? resumed their old life after a sojourn to the Underworld?

You see the quandary our scenario puts to this definition of life, for the waterbear does the exact above. They will suspend their metabolism, which can be considered death, reanimate when harsh environmental conditions subside, and go about their waterbearing ways. Again, do the waterbears live a subset of multiple lives within the set of one life? Quite confusing to think about, yes?

Now let's redefine life.

A waterbear ceases all metabolic activity, resumes it, then lumbers away. In sleep, one's state pre- and post-sleep will differ; one wakes up with changed neuronal connections, yet considers themselves the same person - or not, but let's presume they do. Take, then, the scenario in which one's state pre- and post-sleep does not differ; indeed, neurophysiologically speaking, it appears they've merely paused then recommenced their brain's processes, just as the time 1:31:00 follows 1:30:59.

This suggests that biological life depends not on metabolic function, but on the presence of an organised system of (metabolic) processes. If the system maintains a pristine state, then it matters not how much time has passed since it last operated; the life of the system's organism will end only when when that system becomes so corrupted as to lose the capacity for function. Sufficient corruption might amount to one specalated synapse; it might amount to a missing ganglion. Thus cyrogenics' knottiness.

As to whether they experience verification, you'll have to query a waterbear yourself. More seriously, for any questions on waterbear experience I refer you to a waterbear, or a waterbear philosopher. As to whether and to what degree they experience sensation when undergoing cryptobiosis, we can test to find out, but any results will be interpreted through layers of extrapolation: "Ganglion A was observed inhibiting Ganglion B via neurotransmitter D binding postsynaptic alpha receptors upon tickling the watebear's belly; based on the conclusions of Researchers et. al., this suggests the waterbear experienced either mildly positive or extremely negative sensation."

We'd need to have a means of differentiating the subject waterbear's behaviour from other waterbears; while not exhaustive, classically conditioning a modified reflexive reaction to stimuli (desensitisation, sensitisation) or inducing LTP or LTD on a synapse, then testing whether the adaptations were retained post-reanimation, would be a starting point.

The problem comes when you try to extrapolate success in the above experiment to mean potential for more complex organisms to survive the same procedure given x. Ideally you would image all of the subjects synapses pre-freeze or pre-cryobiosis (depending on what x turns out to be), then image them again post-reanimation, and have a program search for discrepancies. Unfortunately, the closest we are to whole-brain imaging is neuronal fluorescence imaging, which doesn't light up every synapse. Perhaps it might if we use transcranial DC or magnetic stimulation to activate every cell in the brain; doing so may explode a bunch of cells, too. I've just about bent over the conjecture tree by this point.

To keep the information all in one place, I'll reply here.

Cryogenic preservation exists in the proof of tardigrades - also called waterbears - which can reanimate from temperatures as low as 0.15 K, and have sufficient neurophysiological complexity to enable analysis of neuronal structural damage.

We don't know if the identity of a given waterbear pre-cyrobiosis is preserved post-reanimation. For that we'd need a more complex organism. However, the waterbear is idiosyncratic in its capacity for preservation; while it proves the possibility for cyrogenic preservation exists, we ourselves do not have the traits of the waterbear that facilitate its capacity for preservation.

In the human brain, there are billions of synapses - to what neurones other neurones connect, we call the connectome: this informs who you are. According to our current theoretical and practical understanding of how memories work, if synapses degrade even the slightest amount your connectome will change dramatically, and will thus represent a different person - perhaps even a lesser human (fewer memories, etcetera).

Now, let's assume uploading becomes commonplace and you mainly care about preserving your genetic self rather than your developed self (you without most of your memories and different thought processes vs. the person you've endeavoured to become), so any synaptic degradation of subsistence brain areas becomes irrelevant. What will the computer upload? Into what kind of person will your synapses reorganise? Even assuming they will reorganise might ask too much of the hypothetical.

Ask yourself who - or what - you would like to cyropreserve; the more particular your answer, the more science needed to accommodate the possibility.

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