Talk:Information-theoretic death

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This article was the subject of a Wiki Education Foundation-supported course assignment, between 27 August 2019 and 14 December 2019. Further details are available on the course page. Student editor(s): Dcchenn.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 00:32, 17 January 2022 (UTC)

Requested move
The term used in this article (and the quote given therein) is information-theoretic death, rather than "information theoretical death". The hyphen is used to create a compound adjective which reads less clumsily than "information theoretic death" to this native english speaker's eyes. - 69.174.134.88 03:13, 16 June 2006 (UTC)

I support this move.Cryobiologist 18:09, 16 June 2006 (UTC)

Wrong in any case
There is a meaningful concept here but the use of the term "information theoretic" is presumptious and misleading. There is a well established body of knowledge, originally formulated in English and a hard (in the sense of "hard science") mathematical topic and sense associated with the adjectival form of Information Theory and no real connection between it and the subject matter of this article has been established. This is OK but I don't want it to go uncalled that the term "information theoretic death" is anything other than a neologism and not a well founded extrapolation of the mathematical theory of the same name.

Further, it is by no means clear, and on the other hand almost certainly false, that a brain whose process state had been lost by virtue of the cessation of all the electrical activity significant to said process state had avoided "information theoretic death" even in the sense intended.

Lycurgus (talk) 09:24, 12 January 2008 (UTC)


 * It is well-known that only short-term memory depends on electrical activity, otherwise nobody would ever survive cardiac arrest and the rapid loss of brain electrical activity that accompanies it.


 * “We know that secondary memory does not depend on continued activity of the nervous system, because the brain can be totally inactivated by cooling, by general anesthesia, by hypoxia, by ischemia, or by any method, and yet secondary memories that have been previously stored are still retained when the brain becomes active once again. Therefore, secondary memory must result from some actual alterations of the synapses, either physical or chemical.” — Page 658, Textbook of Medical Physiology by Arthur C. Guyton (W.B. Saunders Company, Philadelphia, 1986) Cryobiologist (talk) 21:15, 15 February 2008 (UTC)


 * Typical mindless equivocation on "electrical activity". Obviously no organism can survive the complete cessation of electrical activity in it's CNS and the situations mentioned do not constitute same. Note that only hard freezing as in the crude early cryogenics and not simulated hybernation by hyperthermia come close but these are completely destructive of cells anyway. 74.78.162.229 (talk) 04:54, 8 June 2008 (UTC)


 * This "obviously" is just plain wrong (tardigrades, duh), and it has been proven using vitrification and revival of C elegans that memories persist through cryopreservation. http://www.alcor.org/Library/pdfs/Persistence.of.Long.Term.Memory.in.Vitrified.and.Revived.C.elegans.pdf Lsparrish (talk) 18:36, 8 June 2015 (UTC)


 * A single study in a fringe journal, with literally one day between being received and being accepted (extra-fast peer review) and experimental protocols not detailed in the paper, probably doesn't count as "proven". Perhaps a reproduction or two of the result before claiming proof? (I mean, I'm very pleased someone finally did the obvious experiment, but everything about that paper is low-quality and sloppy.) - David Gerard (talk) 19:56, 8 June 2015 (UTC)


 * Your comprehension of scientific papers is rather suspect, in light of past events. Be that as it may, the cryopreservation protocols referenced are described in different papers. The paper for the vitrification protocol has not yet been published, however both protocols showed signs of memory preservation down to liquid nitrogen temperatures. The slow-freezing method (Brenner, 1974) is said to have around 80% fatality rate, but that didn't stop the survivors from remembering the trained behavior, and is not an obstacle to replication. (Remember, slow freezing just means the cytosol is vitrified, with ice forming between the cells.) Lsparrish (talk) 01:02, 9 June 2015 (UTC)


 * I am researching information theory, and I do not feel that the term "information-theoretic death" is misleading. At least, I have no better idea for the name. I strongly believe that this term is meaningful, we need to have a name of it, and there should be a Wiki page about it. — Preceding unsigned comment added by 193.224.79.242 (talk) 10:40, 19 June 2020 (UTC)

Link to Fiction?
Is it worthwhile to link to the wiki entry for Lem's novel Fiasco? The first part of the book involves a cyrogenics revival - and neither the patient nor his doctors can figure out which of two possible people he might be.

He's forced eventually to assume a third identity. In the context of this article, the original him (whoever him might be) died. - Jason —Preceding unsigned comment added by 71.125.33.112 (talk) 21:41, 12 January 2008 (UTC)

Heisenberg uncertainty principle
I removed the assertion that the Heisenberg uncertainty principle implies imperfect knowledge of a system. This is only true if you insist on thinking of everything as particles. It is in principle possible to have complete knowledge of a wavefunction, assuming perfect instruments (as in an ideal spin-1/2 system after making a measurement). The observer effect or irreversible quantum decoherence might be more relevant challenges to knowing the complete physical state of a brain. --myncknm (talk) 16:39, 8 January 2014 (UTC)

Paragraph before the lead
Before the lead paragraph, there was this thing. I did not understand it and it definitely does not belong before the definition:

In cryonics advocacy, the motivation is to avoid dying, but the patient is clinically dead and thus their body and brain are severely damaged at the point when the procedure is initiated. To complicate matters further, there is significant damage done during cryonics procedures. Thus the entire project is only rational under the assumption that damage can be repaired by future technology. However, given hypothetical the prospect of revival, there can be some confusion about if the person is truly dead or not. — Preceding unsigned comment added by Oracions (talk • contribs) 06:34, 14 July 2015 (UTC)


 * I've noted that "information-theoretic death" is a cryonics jargon term, which should provide sufficient context for the intro - David Gerard (talk) 10:04, 14 July 2015 (UTC)


 * "Jargon" has multiple pejorative connotations (it is hardly an NPOV word), which is the reason why the WP article on jargon has not been merged with technical terminology on WP (see the discussion page at talk:jargon for why). Yes, the WP article on jargon badly needs a rewrite due to this very problem. But that's no excuse for using an egregiously insulting rather than neutral word here. Mr. Gerard, are you sure you didn't mean to write cryonics wacko jargon term? Since that is what you seem to believe, would that not provide even more context? And in addition, you could helpfully use it for all the other stuff for which you are a skeptic. "Skeptic" being a jargon term for "angry disbeliever." S  B Harris 20:15, 21 August 2015 (UTC)

Educating David Gerard
I regret to inform David Gerard that the statement that "Information-theoretic death is a cryonics jargon term" is rather obviously biased.

Even the blander "Information-theoretic death is a cryonics technical terminology term" is incorrect. Quite a few terms are used in cryonics. That does not make them cryonics technology terms. The term "cryogenics", for example, is sometimes used to mean "cryonics", yet all involved know that it has its own distinct meaning and should not be referred to as a "cryonics" term. Nor is the term "molecular repair" a cryonics term, even though this term, too, is frequently applied in the context of cryonics.

One might, with equal justification, call "information-theoretic death" an "uploading jargon term" or "transhumanist jargon term", just as one might call "acceleration" an "artillery jargon term" or an "astronomical jargon term".

In fact, it is none of these things. It is a recognition of the fact that human life can be viewed from the perspective of information, just as almost everything else can be viewed from the perspective of information. Music and sound can be digitized. Paintings and images can be digitized. Videos can be digitized. The human brain can be digitized. We, ourselves, at any moment in time, can be fully described by bits, by 0s and 1s, by information. We are not merely physical objects, we are also abstract entities of information. As long as that information persists, we continue to live. If that information ceases to exist, then we are truly dead.

And now, David, will you please desist in your persistent vandalism of this entry?

RMerkle (talk) 20:45, 21 August 2015 (UTC)

Nobody dies because physics conserves information ?
I deleted the passages that include the claim "resuscitation is not specifically ruled out by the laws of physics, unless information critical to that resuscitation passes beyond the event horizon of a black hole." This assumes that burning a book doesn't erase its contents because in some bizarre sense the text is still contained in fire light photons racing away from Earth. That may be an interesting academic debate for physicists, or even theologians (Omega Point), but it has nothing to do with any use of "information theoretic death" in medical literature, which refers exclusively to technologically accessible information. Cryobiologist (talk) 23:36, 21 August 2015 (UTC)

Reverted edits
I made an edit that simply expresses the fact that the current view of physics is that information is conserved, meaning information-theoretic death is not possible in the absolute sense. A vandal has repeatedly reverted this edit, claiming "there's no proof that's how it works in the brain". I'm not quite sure what this even means, it seems he is quite confused as to what this article is discussing. If information is conserved, then the information in the brain is conserved, and "information-theoretic death" is not possible. If the vandal in question would like to explain what he's talking regarding "how it works in the brain", that would be good. If there are no arguments given I will put my edit back. — Preceding unsigned comment added by 110.175.159.167 (talk • contribs)


 * Please review WP:OR. There is such a thing as conservation of quantum information, but asserting that this happens in brains in any useful or practical sense, such as that discussed in the article, is a novel claim that is in no way supported by the cites. And it really doesn't happen in any useful way in a brain at 310 Kelvins - David Gerard (talk) 07:50, 4 April 2016 (UTC)


 * The brain is a physical entity, and ALL physical information is conserved. What part don't you understand? The temperature of the brain is not relevant at all. If you could show that the brain was not subject to any of the known laws of physics, then you may have a point, however that would be a heterodox view. — Preceding unsigned comment added by 110.175.159.167 (talk • contribs)


 * Indeed, physics works. But does this usefully or practically reflect upon what this page is discussing?
 * Put it this way: if this is actually generally-accepted, you should be able to find multiple high-quality sources saying so. If you can't find said sources, this suggests your conclusion is not backed up - David Gerard (talk) 14:35, 4 April 2016 (UTC)


 * Hi David, I somewhat agree with the original poster. One inevitably comes to this conclusion after asking the question "where do we draw the line" between recoverable and irrecoverable? There appears to be no such line; the amount of mangling suffered by the information only determines how advanced of a technology you'd need to recover it. Let's say we have a piece of paper with text on it. Is the info lost after ripping it to shreds? No because you could put it back together. What about after burning it? Still, a sufficiently super-advanced technology could theoretically analyze every single particle involved in the burning process and trace it back to its original state (like our weather prediction models but billions of times more powerful and run backwards). Theguyi26 (talk) 17:36, 17 October 2017 (UTC)

unsourced bit
This bit is unsourced: moving here til it can be sourced

The use of information-theoretic criteria has formed the basis of ethical arguments that state that cryonics is an attempt to save lives rather than being an interment method for the dead. In contrast, if cryonics cannot be applied before information-theoretic death occurs, or if the cryopreservation procedure itself causes information-theoretic death, then cryonics is not feasible. Exactly when complete and total information-theoretic death might occur with respect to different types of preservation and decomposition might also be relevant to the speculative field of mind uploading.

- Jytdog (talk) 15:45, 4 April 2016 (UTC)

Obsolete scientific information
Reverted edits by Jytdog to the version a few days ago, as the material introduced was obsolete (source dated 2005) and scientifically inaccurate. It is now known that cell damage is (primarily, during short periods) caused not by withdrawal of oxygen, but by the rapid uncontrolled re-introduction of oxygen, and that this process can be delayed or stopped with medically-induced hypothermia. Survival after cardiac arrest can now be extended (in some cases) well after a traditional five-minute or ten-minute window, and skiier Anna Bågenholm survived for over an hour without circulation after falling through ice into frozen water. Links to some of the research in this area:


 * Penn Medicine
 * Prof. Lance Becker in Philadelphia
 * Live Science
 * Newsweek
 * Book on hypothermic medicine
 * Medscape on oxygen toxicity
 * Research into "profound hypothermia"
 * BBC
 * Washington Post
 * Wired
 * New Scientist
 * University of Pennsylvania, again
 * Book by Penn tenured medical professor
 * Medscape overview
 * Review by PubMed
 * Reperfusion injury (Wikipedia summary)
 * Targeted temperature management (Wikipedia summary)

To be clear, none of this means that cryonics will work, or that science or any particular scientist support cryonics. (To my knowledge, most of the researchers in this field are not cryonics supporters.) All the temperatures involved in all of this research were well above the freezing point. However, it's trivial to find reliable mainstream sources (as the above, plus tons of others not mentioned) to support the basic conclusions that:


 * biological death is a continuous process, rather than a single binary event, as in the case of clinical death or legal death
 * the process of death can, in some cases, be reversed by current medical technology well after the onset of clinical death
 * the process of death, in general, happens more slowly under colder temperatures
 * cells, including brain neurons, do not automatically undergo apoptosis after a few minutes without oxygen

In addition, I should note the following smaller inaccuracies:


 * the version by Jytdog says that "speculates about a future in which people could be preserved with cyronics", but (in addition to the misspelling) this is inaccurate; it is indisputably true that people are being preserved with cryonics, the speculative part is whether cryonics patients can be revived
 * "information-theoretic death" is not a theory, but merely defines a term. Falsifiability is necessary for an idea to be considered a theory, and "information-theoretic death" is not falsifiable, any more than clinical death or legal death are falsifiable; they're just definitions
 * "information" should not be in scare quotes, as it's undisputed (I hope) that the brain does in fact contain information; "Barack Obama was born in 1961", for example, is obviously information contained in the brain
 * "[Merkle's] theory opposes itself to clinical death and legal death" is unsourced, doesn't seem to be anywhere in Merkle's papers, and doesn't make much sense; one wouldn't say that #1122FF and #2211FF were "opposed", even though they're different definitions of the color "blue", they're just different descriptors for different things. Merkle opposes the idea that everyone who is clinically dead or brain dead is "gone for good" and can never be brought back, but (per everything above) no one seriously disputes this; see also eg. here or here or here or here or here
 * the sentence beginning "Merkle further suggested" is cited to Merkle's paper, but is also cited to someone else named Wowk; it's not clear how this supports "Merkle further suggested", presumably any of Wowk's claims are his own and should be attributed to him

Essentially, the semantic question of how to define the word "death" is mixed up with the factual question of whether certain people do or don't meet certain definitions of death, which is mixed up with the scientific question of how likely people in various states are to return to normal life, which is mixed up with speculation about how those odds might change in the future. I'd tentatively suggest trying to merge this mess into the article at Medical definition of death. It's clear that (for whatever reason) few or none of the scientists in this area are using Merkle's term, so it might be impossible to keep an article on information-theoretic death up-to-date without doing original research. If, eg., tomorrow scientists discovered that people could be taken to 5 C body temperature and survive, this would prove that such people were not "information-theoretically dead" as Merkle defines it, but the article couldn't say that because (almost certainly) none of the sources would actually use that term. NeatGrey (talk) 04:41, 5 April 2016 (UTC)
 * Thanks for pointing out some of those issues. I just worked on most of them.  I like the idea of merging this article into medical definition of death.  that is a much better option than what we have here.  shall we? Jytdog (talk) 05:28, 5 April 2016 (UTC)
 * Done, I've merged and redirected. Actually, that article itself could use quite a bit of work. I'll start by breaking up that huge paragraph under brain death... NeatGrey (talk) 05:57, 5 April 2016 (UTC)
 * The redirect heads to Legal death which this topic obviously doesn't fall under. Changing back. Not sure why you thought the redirect to Medical definition of death would have made sense anyway.Lsparrish (talk) 14:09, 23 May 2016 (UTC)

New web page on information-theoretic death
It is with sadness that I have observed the systematic degradation of Wikipedia's web page on information-theoretic death. By deleting relevant references that clearly meet Wikipedia's standards for references, by violating Wikipedia's NPV, and generally by ignoring the core concepts behind Wikipedia, intellectual vandals have brought us to the point where the Wikipedia web page on this subject is no longer useful. As a consequence, I have created a new web page on my own web site on information-theoretic death: http://www.merkle.com/definitions/infodeath.html. I would recommend that anyone who wishes to link to a stable and reasonable web page on information-theoretic death link to my page. I would encourage Wikipedia editors to revert this page to an earlier (less damaged) version, and then update it. There will, however, have to be some watch kept on the vandals. RMerkle (talk) 16:48, 4 June 2016 (UTC)

History - WP:SYN
This is SYN

Focus on the brain for defining death under certain conditions began in the mid 20th century when it became possible to artificially replace functions of the heart and lungs. By the 1960s, it was possible to artificially maintain circulation and breathing even while the brain decomposed. This led to a new kind of death called brain death. Brain death came to diagnosed by neurologic examination noting clinical absence of brain functions without presence of confounding factors known to reversibly inhibit brain activity. Early in the history of brain death, there was recognition that clinical findings of brain death were accompanied by alteration or loss of the physical cell structure of the brain. However the nature and extent of the physical change or "destruction" were highly variable, especially in later decades when delays between brain death diagonses and removal from ventilator support became shorter because of organ donation. By the late 1970s it was suggested by some that brain death should be defined in terms of "structural destruction" or "total brain destruction" because it was the only obviously sufficient physical condition to eliminate the possibility of brain function returning "now or in the future," Others advocated "irreversible loss of anatomical brain structure at the cellular level" as a definition of death, without elaboration of "irreversible."
 * History

In 1992, in a paper about the controversial field of cryonics in the then non-peer-reveiwed journal Medical Hypotheses, cryptography pioneer and molecular nanotechnology researcher Ralph Merkle argued that brain destruction need not be total for resuscitation of a person to be impossible by physical law. Merkle propsed that loss of brain detail encoding long-term memory and personality in an information-theoretic sense was both necessary and sufficient for permanent death of a person. Loss in an information-theoretic sense meant that the state of a brain had been so disturbed that it was theoretically impossible to infer a preceding brain state corresponding to a unique individual. He called such a criterion for death, the information theoretic criterion of death. Unlike definitions of death that evolve with changing technology, Merkle intended his conceptual definition death to be timeless; a threshold of neurological damage beyond which no possible future technology could recover the original person who died.

-- Jytdog (talk) 15:00, 10 June 2016 (UTC)

Usage - more SYN
This is too is created here in WP in a work of synthesis

Information-theoretic death is not a term used in clinical medicine because it is a concept, not a diagnosable state. It has been used in philosophical and ethical discussions of organ donation, brain death,      and controversial brain preservation technologies such as cryonics    and mind uploading. The first occurrences  of information-theoretic death in peer-reviewed scientific literature were in discussions of a type of organ donation called Donation After Cardiac Death (DCD), also called Non-heart-beating donation (NHBD). In DCD, organs are removed from terminally-ill people declared dead based on stopped heartbeat (cardiopulmonary death) rather than brain death. In DCD, organ retrieval is begun after heartbeat and blood circulation are stopped for 75 seconds to 5 minutes. This waiting period is for the heart to become damaged enough by lack of oxygen to not be able to spontaneously restart within the donor(autoresuscitation), but undamaged enough for the heart and other organs to later resume function inside the organ recipient. The implied possibility of restarting cardiac and brain activity within the donor after such cardiopulmonary death declaration has generated ethical debate about whether DCD might violate the Dead Donor Rule of organ donation A key issue in these discussions has been whether the word irreversible in the cardiopulmonary death definition of the United States Uniform Determination of Death Act should be interpreted to mean not spontaneously reversible (autoresuscitation) or interpreted to mean not reversible by intervention. In DCD debate, "information-theoretic death" as defined by Merkle has been mentioned as an attempt to craft a definition of death that is rigorous rather than utilitarian, and as a "third" type of irreversibility, beyond impossibility of autresuscitation and beyond impossibility of active cardiac resuscitation, rooted instead in laws of physics.
 * Usage

Information-theoretic death has also appeared in some discussions of brain death,    a type of death in which brain structure has long been part of bioethical discussion, even if not useable for clinical diagnosis. A particular context in which the question of information-theoretic death has been raised is the potential use of neuroremediation and regenerative medicine technologies on end-stage dementia or even "brain dead" patients to restore normal neurological function. Such technologies raise complex questions, such as whether restored minds would be those of the same people as before the brain disease or injury that had been treated.


 * Notes

-- Jytdog (talk) 15:02, 10 June 2016 (UTC)

WP:OR with primary sources
This is commenting/interpreting primary sources in a way that is not valid in WP

Information-theoretic death is a definition, not a hypothesis. The definition of information-theoretic death is silent about what physical brain attributes encode memory, personality, or any other information upon which personal identity depends. The definition is similarly silent about circumstances under which this information is lost. The only assumption is that a unique personhood, or personal identity, is reflected in a brain with uniqueness that becomes theoretically impossible to recover after sufficient damage.
 * Physical correlates

Like other brain criteria for death, information-theoretic death is not coincident with cardiac death. Types of brain damage that have been speculated to correlate with information theoretic death have included a few hours, or possibly "many hours," of stopped blood circulation (ischemia), clinical brain death, connectome loss, advanced or complete autolysis of the brain, and, trivially, cremation.

-- Jytdog (talk) 15:04, 10 June 2016 (UTC)

From criticisms section...
Not sure what this is trying to say. Some of these sources are not about information-theoretic death

While information-theoretic death is not unique in focusing on brain structure loss as a philosophical criterion for death, the criterion is unusual for its origination in the context of an argument that anyone who is not information-theoretically dead could actually be revived. Although some ethical thought experiments involving information-theoretic death utilize emerging medical technologies, such as stem cells, others envision highly advanced molecular nanotechnology. It is suggested that the detailed molecular state of a brain and stored memories is not just something to ponder philosophically, but that in the future it may be possible to know and repair this state literally, making possible actual resuscitation of anyone who isn't information-theoretically dead. Not everyone in the scientific community takes such ideas seriously, and the possibility and practicality of such future technology has been questioned.

--Jytdog (talk) 15:09, 10 June 2016 (UTC)

Improper synthesis
I removed a section of text which appears to me to be a novel synthesis. Example: "Information-theoretic death has propagated into some mainstream bioethical, biophilosophical and religious discussions of death," but the actual sources appear to be talking about the ethical impact of differences in brain death criteria between countries. Additionally, many of the sources don't meet WP:MEDRS. This gives the appearance of having trawled the internet for every single mention of the term and cramming them into a sentence. I'm not seeing any high level review articles about it, as MEDRS would require. Books published by minor publishers are not really the thing. The most we can say is that a small number of minor publications have discussed this, but really we need an independent source even for that. Guy (Help!) 13:25, 24 January 2019 (UTC)

section just added and removed
This is a lengthy section that was sourced to (a) Merkle's web page (b) an apparent pseudojournal https://jetpress.org/ that says it's "peer reviewed" but is actually a transhumanist advocacy site run by the IEET. I'm pretty sure neither of these is suitable for an article under WP:MEDRS - David Gerard (talk) 07:56, 5 December 2019 (UTC)

Restored article
This article was redirected to Cryonics without discussion. Since this article has been kept in AfDs twice, and the target does not directly mention the subject, I am restoring the page. ilmaisin (talk) 21:06, 27 January 2024 (UTC)