Immortality is eternal life, the ability to live forever. Biological forms have inherent limitations which medical interventions or engineering may or may not be able to overcome. Natural selection has developed potential biological immortality in at least one species, the jellyfish Turritopsis dohrnii.
Certain scientists, futurists, and philosophers, have theorized about the immortality of the human body, and advocate that human immortality is achievable in the first few decades of the 21st century, while other advocates believe that life extension is a more achievable goal in the short term, with immortality awaiting further research breakthroughs into an indefinite future. Aubrey de Grey, a researcher who has developed a series of biomedical rejuvenation strategies to reverse human aging (called SENS), believes that his proposed plan for ending aging may be implementable in two or three decades. The absence of aging would provide humans with biological immortality, but not invulnerability to death by physical trauma. What form an unending human life would take, or whether an immaterial soul exists and possesses immortality, has been a major point of focus of religion, as well as the subject of speculation, fantasy, and debate.
- 1 Definitions
- 2 Alchemy
- 3 Physical immortality
- 3.1 Causes of death
- 3.2 Biological immortality
- 3.3 Prospects for human biological immortality
- 4 Religious views
- 5 Ethics of immortality
- 6 Politics
- 7 Symbols
- 8 Fiction
- 9 See also
- 10 References
- 11 Further reading
- 12 External links
Life extension technologies promise a path to complete rejuvenation. Cryonics holds out the hope that the dead can be revived in the future, following sufficient medical advancements. While, as shown with creatures such as hydra and planarian worms, it is indeed possible for a creature to be biologically immortal, it is not yet known if it is possible for humans.
Mind uploading is the transference of consciousness from a human brain to an alternative medium providing the same functionality. Assuming the process to be possible and repeatable, this would provide immortality to the consciousness, as predicted by futurists such as Ray Kurzweil.
The belief in an afterlife is a fundamental tenet of most religions, including Hinduism, Sikhism, Christianity, Zoroastrianism, Islam, Judaism, and the Bahá'í Faith; however, the concept of an immortal soul is not. The "soul" itself has different meanings and is not used in the same way in different religions and different denominations of a religion. For example, various branches of Christianity have disagreeing views on the soul's immortality and its relation to the body.
Physical immortality is a state of life that allows a person to avoid death and maintain conscious thought. It can mean the unending existence of a person from a physical source other than organic life, such as a computer. Active pursuit of physical immortality can either be based on scientific trends, such as cryonics, digital immortality, breakthroughs in rejuvenation or predictions of an impending technological singularity, or because of a spiritual belief, such as those held by Rastafarians or Rebirthers.
Causes of death
Aubrey de Grey, a leading researcher in the field, defines aging as "a collection of cumulative changes to the molecular and cellular structure of an adult organism, which result in essential metabolic processes, but which also, once they progress far enough, increasingly disrupt metabolism, resulting in pathology and death." The current causes of aging in humans are cell loss (without replacement), DNA damage, oncogenic nuclear mutations and epimutations, cell senescence, mitochondrial mutations, lysosomal aggregates, extracellular aggregates, random extracellular cross-linking, immune system decline, and endocrine changes. Eliminating aging would require finding a solution to each of these causes, a program de Grey calls engineered negligible senescence. There is also a huge body of knowledge indicating that change is characterized by the loss of molecular fidelity.
Disease is theoretically surmountable via technology. In short, it is an abnormal condition affecting the body of an organism, something the body shouldn't typically have to deal with its natural make up. Human understanding of genetics is leading to cures and treatments for myriad previously incurable diseases. The mechanisms by which other diseases do their damage are becoming better understood. Sophisticated methods of detecting diseases early are being developed. Preventative medicine is becoming better understood. Neurodegenerative diseases like Parkinson's and Alzheimer's may soon be curable with the use of stem cells. Breakthroughs in cell biology and telomere research are leading to treatments for cancer. Vaccines are being researched for AIDS and tuberculosis. Genes associated with type 1 diabetes and certain types of cancer have been discovered, allowing for new therapies to be developed. Artificial devices attached directly to the nervous system may restore sight to the blind. Drugs are being developed to treat myriad other diseases and ailments.
Physical trauma would remain as a threat to perpetual physical life, even if the problems of aging and disease were overcome, as an otherwise immortal person would still be subject to unforeseen accidents or catastrophes. The speed and quality of paramedic response remains a determining factor in surviving severe trauma. A body that could automatically repair itself from severe trauma, such as speculated uses for nanotechnology, would mitigate this factor. Being the seat of consciousness, the brain cannot be risked to trauma if a continuous physical life is to be maintained. Therefore, it cannot be replaced or repaired in the same way other organs can.
If there is no limitation on the degree of gradual mitigation of risk then it is possible that the cumulative probability of death over an infinite horizon is less than certainty, even when the risk of fatal trauma in any finite period is greater than zero. Mathematically, this is an aspect of achieving "Actuarial escape velocity".
Biological immortality is an absence of aging, specifically the absence of a sustained increase in rate of mortality as a function of chronological age. A cell or organism that does not experience aging, or ceases to age at some point, is biologically immortal.
Biologists have chosen the word immortal to designate cells that are not limited by the Hayflick limit, where cells no longer divide because of DNA damage or shortened telomeres. The first and still most widely used immortal cell line is HeLa, developed from cells taken from the malignant cervical tumor of Henrietta Lacks without her consent in 1951. Prior to the 1961 work of Leonard Hayflick and Paul Moorhead, there was the erroneous belief fostered by Alexis Carrel that all normal somatic cells are immortal. By preventing cells from reaching senescence one can achieve biological immortality; telomeres, a "cap" at the end of DNA, are thought to be the cause of cell aging. Every time a cell divides the telomere becomes a bit shorter; when it is finally worn down, the cell is unable to split and dies. Telomerase is an enzyme which rebuilds the telomeres in stem cells and cancer cells, allowing them to replicate an infinite number of times. No definitive work has yet demonstrated that telomerase can be used in human somatic cells to prevent healthy tissues from aging. On the other hand, scientists hope to be able to grow organs with the help of stem cells, allowing organ transplants without the risk of rejection, another step in extending human life expectancy. These technologies are the subject of ongoing research, and are not yet realized.
Biologically immortal species
Life defined as biologically immortal is still susceptible to causes of death besides aging, including disease and trauma, as defined above. Notable immortal species include:
- Turritopsis nutricula, a jellyfish, after becoming a sexually mature adult, can transform itself back into a polyp using the cell conversion process of transdifferentiation. Turritopsis nutricula repeats this cycle, meaning that it may have an indefinite lifespan. Its immortal adaptation has allowed it to spread from its original habitat in the Caribbean to "all over the world".
- Bacteria – Bacteria reproduce through binary fission. A parent bacterium splits itself into two identical daughter cells which eventually then split themselves in half. This process repeats, thus making the bacterium essentially immortal. A 2005 PLoS Biology paper suggests that after each division the daughter cells can be identified as the older and the younger, and the older is slightly smaller, weaker, and more likely to die than the younger.
- Bristlecone pines are speculated to be potentially immortal; the oldest known living specimen is over 5,000 years old.
- Hydra is a genus of simple fresh-water animal possessing radial symmetry. Hydras are predatory animals belonging to the phylum Cnidaria and the class Hydrozoa.
Evolution of aging
As the existence of biologically immortal species demonstrates, there is no thermodynamic necessity for senescence: a defining feature of life is that it takes in free energy from the environment and unloads its entropy as waste. Living systems can even build themselves up from seed, and routinely repair themselves. Aging is therefore presumed to be a byproduct of evolution, but why mortality should be selected for remains a subject of research and debate. Programmed cell death and the telomere "end replication problem" are found even in the earliest and simplest of organisms. This may be a tradeoff between selecting for cancer and selecting for aging.
Modern theories on the evolution of aging include the following:
- Mutation accumulation is a theory formulated by Peter Medawar in 1952 to explain how evolution would select for aging. Essentially, aging is never selected against, as organisms have offspring before the mortal mutations surface in an individual.
- Antagonistic pleiotropy is a theory proposed as an alternative by George C. Williams, a critic of Medawar, in 1957. In antagonistic pleiotropy, genes carry effects that are both beneficial and detrimental. In essence this refers to genes that offer benefits early in life, but exact a cost later on, i.e. decline and death.
- The disposable soma theory was proposed in 1977 by Thomas Kirkwood, which states that an individual body must allocate energy for metabolism, reproduction, and maintenance, and must compromise when there is food scarcity. Compromise in allocating energy to the repair function is what causes the body gradually to deteriorate with age, according to Kirkwood.
Prospects for human biological immortality
Scientists believe that boosting the amount or proportion of in the body of telomerase, a naturally forming enzyme that helps maintain the protective caps at the ends of chromosomes, could prevent cells from dying and so may ultimately lead to extended, healthier lifespans. A team of researchers at the Spanish National Cancer Centre (Madrid) tested the hypothesis on mice. It was found that those mice which were genetically engineered to produce 10 times the normal levels of telomerase lived 50% longer than normal mice.
In normal circumstances, without the presence of telomerase, if a cell divides repeatedly, at some point all the progeny will reach their Hayflick limit. With the presence of telomerase, each dividing cell can replace the lost bit of DNA, and any single cell can then divide unbounded. While this unbounded growth property has excited many researchers, caution is warranted in exploiting this property, as exactly this same unbounded growth is a crucial step in enabling cancerous growth. If an organism can replicate its body cells faster, then it would theoretically stop aging.
Embryonic stem cells express telomerase, which allows them to divide repeatedly and form the individual. In adults, telomerase is highly expressed in cells that need to divide regularly (e.g., in the immune system), whereas most somatic cells express it only at very low levels in a cell-cycle dependent manner.
Technological immortality is the prospect for much longer life spans made possible by scientific advances in a variety of fields: nanotechnology, emergency room procedures, genetics, biological engineering, regenerative medicine, microbiology, and others. Contemporary life spans in the advanced industrial societies are already markedly longer than those of the past because of better nutrition, availability of health care, standard of living and bio-medical scientific advances. Technological immortality predicts further progress for the same reasons over the near term. An important aspect of current scientific thinking about immortality is that some combination of human cloning, cryonics or nanotechnology will play an essential role in extreme life extension. Robert Freitas, a nanorobotics theorist, suggests tiny medical nanorobots could be created to go through human bloodstreams, find dangerous things like cancer cells and bacteria, and destroy them. Freitas anticipates that gene-therapies and nanotechnology will eventually make the human body effectively self-sustainable and capable of living indefinitely, short of severe brain trauma. This supports the theory that we will be able to continually create biological or synthetic replacement parts to replace damaged or dying ones.
Cryonics, the practice of preserving organisms (either intact specimens or only their brains) for possible future revival by storing them at cryogenic temperatures where metabolism and decay are almost completely stopped, can be used to 'pause' for those who believe that life extension technologies will not develop sufficiently within their lifetime. Ideally, cryonics would allow clinically dead people to be brought back in the future after cures to the patients' diseases have been discovered and aging is reversible. Modern cryonics procedures use a process called vitrification which creates a glass-like state rather than freezing as the body is brought to low temperatures. This process reduces the risk of ice crystals damaging the cell-structure, which would be especially detrimental to cell structures in the brain, as their minute adjustment evokes the individual's mind.
One idea that has been advanced involves uploading an individual's personality and memories via direct mind-computer interface. The individual's memory may be loaded to a computer or to a newly born baby's mind. The baby will then grow with the previous person's individuality, and may not develop its own personality. Extropian futurists like Moravec and Kurzweil have proposed that, thanks to exponentially growing computing power, it will someday be possible to upload human consciousness onto a computer system, and live indefinitely in a virtual environment. This could be accomplished via advanced cybernetics, where computer hardware would initially be installed in the brain to help sort memory or accelerate thought processes. Components would be added gradually until the person's entire brain functions were handled by artificial devices, avoiding sharp transitions that would lead to issues of identity. After this point, the human body could be treated as an optional accessory and the mind could be transferred to any sufficiently powerful computer. Another possible mechanism for mind upload is to perform a detailed scan of an individual's original, organic brain and simulate the entire structure in a computer. What level of detail such scans and simulations would need to achieve to emulate consciousness, and whether the scanning process would destroy the brain, is still to be determined. Whatever the route to mind upload, persons in this state would then be essentially immortal, short of loss or traumatic destruction of the machines that maintained them.
Transforming a human into a cyborg can include brain implants or extracting a human mind and placing it in a robotic life-support system. Even replacing biological organs with robotic ones could increase life span (i.e., pace makers) and depending on the definition, many technological upgrades to the body, like genetic modifications or the addition of nanobots would qualify an individual as a cyborg. Such modifications would make one impervious to aging and disease and theoretically immortal unless killed or destroyed.
Another approach, developed by biogerontologist Marios Kyriazis, holds that human biological immortality is an inevitable consequence of evolution. As the natural tendency is to create progressively more complex structures, there will be a time (Kyriazis claims this time is now), when evolution of a more complex human brain will be faster via a process of developmental singularity rather than through Darwinian evolution. In other words, the evolution of the human brain as we know it will cease and there will be no need for individuals to procreate and then die. Instead, a new type of development will take over, in the same individual who will have to live for many centuries in order for the development to take place. This intellectual development will be facilitated by technology such as synthetic biology, artificial intelligence and a technological singularity process.
The world's major religions hold a number of perspectives on spiritual immortality, the unending existence of a person from a nonphysical source or in a nonphysical state such as a soul. However any doctrine in this area misleads without a prior definition of "soul". Another problem is that "soul" is often confused and used synonymously or interchangeably with "spirit".
As late as 1952, the editorial staff of the Syntopicon found in their compilation of the Great Books of the Western World, that "The philosophical issue concerning immortality cannot be separated from issues concerning the existence and nature of man's soul." Thus, the vast majority of speculation regarding immortality before the 21st century was regarding the nature of the afterlife.
In both Western and Eastern religions, the spirit is an energy or force that transcends the mortal body, and returns to the spirit realm whether to enjoy heavenly bliss or suffer eternal torment in hell, or the cycle of life, directly or indirectly depending on the tradition.
Ancient Greek religion
In ancient Greek religion, immortality originally always included an eternal union of body and soul, as can be seen in Homer, Hesiod, and various other ancient texts. The soul was considered to have an eternal existence in Hades, but without the body the soul was considered dead. Although almost everybody had nothing to look forward to but an eternal existence as a disembodied dead soul, a number of men and women were considered to have gained physical immortality and been brought to live forever in either Elysium, the Islands of the Blessed, heaven, the ocean or literally right under the ground. Among these were Amphiaraus, Ganymede, Ino, Iphigenia, Menelaus, Peleus, and a great part of those who fought in the Trojan and Theban wars. Some were considered to have died and been resurrected before they achieved physical immortality. Asclepius was killed by Zeus only to be resurrected and transformed into a major deity. Achilles, after being killed, was snatched from his funeral pyre by his divine mother Thetis, resurrected, and brought to an immortal existence in either Leuce, the Elysian plains, or the Islands of the Blessed. Memnon, who was killed by Achilles, seems to have a received a similar fate. Alcmene, Castor, Heracles, and Melicertes were also among the figures sometimes considered to have been resurrected to physical immortality. According to Herodotus' Histories, the 7th century BC sage Aristeas of Proconnesus was first found dead, after which his body disappeared from a locked room. Later he was found not only to have been resurrected but to have gained immortality.
The philosophical idea of an immortal soul was a belief first appearing with either Pherecydes or the Orphics, and most importantly advocated by Plato and his followers. This, however, never became the general norm in Hellenistic thought. As may be witnessed even into the Christian era, not least by the complaints of various philosophers over popular beliefs, many or perhaps most traditional Greeks maintained the conviction that certain individuals were resurrected from the dead and made physically immortal and that others could only look forward to an existence as disembodied and dead, though everlasting, souls. The parallel between these traditional beliefs and the later resurrection of Jesus was not lost on the early Christians, as Justin Martyr argued: "when we say ... Jesus Christ, our teacher, was crucified and died, and rose again, and ascended into heaven, we propose nothing different from what you believe regarding those whom you consider sons of Zeus." (1 Apol. 21).
Individuals claiming to be physically immortal include Comte de Saint-Germain; in 18th century France, he claimed to be centuries old, and people who adhere to the Ascended Master Teachings are convinced of his physical immortality.
Desiring a soul or ego (ātman) to be permanent is a prime consequence of ignorance, itself the cause of all misery and the foundation of the cycle of rebirth (saṃsāra). Form and consciousness being two of the five skandhas, or aggregates of ignorance, Buddhism teaches that physical immortality is neither a path to enlightenment, nor an attainable goal, even the gods which can live for eons eventually die. Upon enlightenment, the "karmic seeds" (saṅkhāras or sanskaras) for all future becoming and rebirth are exhausted. After biological death an arhat, or buddha, enters into parinirvana, a state of deathlessness due to the absence of rebirth, which resulted from cessation of wantings.
Buddhism teaches that there is a cycle of birth, death, and rebirth and that the process is according to the qualities of a person's actions. This constant process of becoming ceases at the fruition of Bodhi (enlightenment) at which a being is no longer subject to causation (karma) but enters into a state that the Buddha called amata (deathlessness).
According to the philosophical premise of the Buddha, the initiate to Buddhism who is to be "shown the way to Immortality (amata)", wherein liberation of the mind (cittavimutta) is effectuated through the expansion of wisdom and the meditative practices of sati and samādhi, must first be educated away from his former ignorance-based (avijja) materialistic proclivities in that he "saw any of these forms, feelings, or this body, to be my Self, to be that which I am by nature".
Christian theology holds that Adam and Eve lost physical immortality for themselves and all their descendants in the Fall of Man, although this initial "imperishability of the bodily frame of man" was "a preternatural condition".
Born-again Christians believe that after the Last Judgment, those who have been "born again" will live forever in the presence of God, and those who were never "born again" will be abandoned to never-ending consciousness of guilt, separation from God, and punishment for sin. Eternal death is depicted in the Bible as a realm of constant physical and spiritual anguish in a lake of fire, and a realm of darkness away from God. Some see the fires of Hell as a theological metaphor, representing the inescapable presence of God endured in absence of love for God; others suggest that Hell represents complete destruction of both the physical body and of spiritual existence.
N.T. Wright, a theologian and former Bishop of Durham, has said many people forget the physical aspect of what Jesus promised. He told Time: "Jesus' resurrection marks the beginning of a restoration that he will complete upon his return. Part of this will be the resurrection of all the dead, who will 'awake', be embodied and participate in the renewal. John Polkinghorne, a physicist and a priest, has put it this way: 'God will download our software onto his hardware until the time he gives us new hardware to run the software again for ourselves.' That gets to two things nicely: that the period after death (the Intermediate state) is a period when we are in God's presence but not active in our own bodies, and also that the more important transformation will be when we are again embodied and administering Christ's kingdom." This kingdom will consist of Heaven and Earth "joined together in a new creation", he said. Bible passages like 1 Corinthians 15 are interpreted as teaching that the resurrected body will, like the present body, be both physical (but a renewed and non-decaying physical body) and spiritual.
Specific imagery of resurrection into immortal form is found in the Pauline letters:
Behold, I shew you a mystery; We shall not all sleep, but we shall all be changed,
In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed.
For this corruptible must put on incorruption, and this mortal must put on immortality.
So when this corruptible shall have put on incorruption, and this mortal shall have put on immortality, then shall be brought to pass the saying that is written, Death is swallowed up in victory.
O death, where is thy sting? O grave, where is thy victory?
The sting of death is sin; and the strength of sin is the law.
But thanks be to God, which giveth us the victory through our Lord Jesus Christ.
Therefore, my beloved brethren, be ye stedfast, unmoveable, always abounding in the work of the Lord, forasmuch as ye know that your labour is not in vain in the Lord.
Hindus believe in an immortal soul which is reincarnated after death. According to Hinduism, people repeat a process of life, death, and rebirth in a cycle called samsara. If they live their life well, their karma improves and their station in the next life will be higher, and conversely lower if they live their life poorly. After many life times of perfecting its karma, the soul is freed from the cycle and lives in perpetual bliss.
There is no place of eternal torment in Hinduism, although if a soul consistently lives very evil lives, it could work its way down to the very bottom of the cycle.
There are explicit renderings in the Upanishads alluding to a physically immortal state brought about by purification, and sublimation of the 5 elements that make up the body. For example in the Shvetashvatara Upanishad (Chapter 2, Verse 12), it is stated "When earth, water fire, air and akasa arise, that is to say, when the five attributes of the elements, mentioned in the books on yoga, become manifest then the yogi's body becomes purified by the fire of yoga and he is free from illness, old age and death."
The above phenomenon is possible when the soul reaches enlightenment while the body and mind are still intact, an extreme rarity, and can only be achieved upon the highest most dedication, meditation and consciousness.
Another view of immortality is traced to the Vedic tradition by the interpretation of Maharishi Mahesh Yogi:
That man indeed whom these (contacts)
do not disturb, who is even-minded in
pleasure and pain, steadfast, he is fit
for immortality, O best of men.
To Maharishi Mahesh Yogi, the verse means, "Once a man has become established in the understanding of the permanent reality of life, his mind rises above the influence of pleasure and pain. Such an unshakable man passes beyond the influence of death and in the permanent phase of life: he attains eternal life ... A man established in the understanding of the unlimited abundance of absolute existence is naturally free from existence of the relative order. This is what gives him the status of immortal life."
|This section may need to be rewritten entirely to comply with Wikipedia's quality standards. (February 2014)|
Muslims believe that the present life is a trial in preparation for the next realm of existence. Muslims believe that everyone will be resurrected after death. Those who believed in Islam and led an evil life will undergo correction in Jahannam (Hell) but once this correction is over, they are admitted to Jannah (Paradise) and attain immortality. Infidels and those who committed unforgivable evil will never leave Hell.
- He says [man says], "Who will give life to bones while they are disintegrated?" Say, "He will give them life who produced them the first time; and He is, of all creation, Knowing." [It is Allah] He who made for you from the green tree, fire, and then from it you ignite. Is not He who created the heavens and the earth Able to create the likes of them? Yes, [it is so]; and He is the Knowing Creator. (Quran, 36:78–81)
- But those who disbelieve say, "The Hour (i.e., the Day of Judgment) will not come to us." Say, "Yes, by my Lord, it will surely come to you. [Allah is] the Knower of the unseen." Not absent from Him is an atom's weight within the heavens or within the earth or [what is] smaller than that or greater, except that it is in a clear register – That He may reward those who believe and do righteous deeds. Those will have forgiveness and noble provision. But those who strive against Our verses [seeking] to cause failure (i.e., to undermine their credibility) – for them will be a painful punishment of foul nature. (Quran, 34:3–5)
- And they say [non-believers in Allah], "There is not but our worldly life; we die and live
(i.e., some people die and others live, replacing them) and nothing destroys us except time."
- And when Our verses are recited to them as clear evidences, their argument is only that they say,
"Bring [back] our forefathers, if you should be truthful."
Say, "Allah causes you to live, then causes you to die; then He will assemble you for the Day of Resurrection,
about which there is no doubt," but most of the people do not know.(Quran, 45:24–26)
- "How can ye reject the faith in Allah?- seeing that ye were without life, and He gave you life; then will He cause you to die, and will again bring you to life; and again to Him will ye return."(Quran,002.028)
|This section may need to be rewritten entirely to comply with Wikipedia's quality standards. (February 2014)|
Judaism claims that the righteous dead will be resurrected in the Messianic age with the coming of the messiah. They will then be granted immortality in a perfect world. The wicked dead, on the other hand, will not be resurrected at all. This is not the only Jewish belief about the afterlife. The Tanakh is not specific about the afterlife, so there are wide differences in views and explanations among believers.
The Hebrew Bible speaks about Sheol (שאול), originally a synonym of the grave-the repository of the dead or the cessation of existence until the Resurrection. This doctrine of resurrection is mentioned explicitly only in Daniel 12:1–4 although it may be implied in several other texts. New theories arose concerning Sheol during the intertestamental literature. Some Hellenistic Jews postulated that the soul (nefesh נפש) was really immortal and that Sheol was actually a destination of the dead awaiting the Resurrection, a syncretic form of Platonic Philosophy. By the 2nd century BC, Jews who accepted the Oral Torah had come to believe that those in Sheol awaited the resurrection either in Paradise (in the bosom of Abraham) or in Torment (Tartarus).
Rastafarians believe in physical immortality as a part of their religious doctrines. They believe that after God has called the Day of Judgment they will go to what they describe as Mount Zion in Africa to live in freedom forever. They avoid the term "everlasting life" and deliberately use "ever-living" instead.
It is repeatedly stated in Lüshi Chunqiu that death is unavoidable. Henri Maspero noted that many scholarly works frame Taoism as a school of thought focused on the quest for immortality. Isabelle Robinet asserts that Taoism is better understood as a way of life than as a religion, and that its adherents do not approach or view Taoism the way non-Taoist historians have done. In the Tractate of Actions and their Retributions, a traditional teaching, spiritual immortality can be rewarded to people who do a certain amount of good deeds and live a simple, pure life. A list of good deeds and sins are tallied to determine whether or not a mortal is worthy. Spiritual immortality in this definition allows the soul to leave the earthly realms of afterlife and go to pure realms in the Taoist cosmology.
Zoroastrians believe that on the fourth day after death, the human soul leaves the body and the body remains as an empty shell. Souls would go to either heaven or hell; these concepts of the afterlife in Zoroastrianism may have influenced Abrahamic religions. The word immortal is driven from the month "Amurdad", meaning "deathless" in Persian, in the Iranian calendar (near the end of July). The month of Amurdad or Ameretat is celebrated in Persian culture as ancient Persians believed the "Angel of Immortality" won over the "Angel of Death" in this month.
Ethics of immortality
The possibility of clinical immortality raises a host of medical, philosophical, and religious issues and ethical questions. These include persistent vegetative states, the nature of personality over time, technology to mimic or copy the mind or its processes, social and economic disparities created by longevity, and survival of the heat death of the universe.
Undesirability of immortality
The doctrine of immortality is essential to many of the world's religions. Narratives from Christianity and Islam assert that immortality is not desirable to the unfaithful:
The poor man died and was carried away by the angels to be with Abraham. The rich man also died and was buried. In Hades, where he was being tormented, he looked up and saw Abraham far away with Lazarus by his side. He called out, 'Father Abraham, have mercy on me, and send Lazarus to dip the tip of his finger in water and cool my tongue; for I am in agony in these flames.' But Abraham said, 'Child, remember that during your lifetime you received your good things, and Lazarus in like manner evil things; but now he is comforted here, and you are in agony. Besides all this, between you and us a great chasm has been fixed, so that those who might want to pass from here to you cannot do so, and no one can cross from there to us.'
Those who are wretched shall be in the Fire: There will be for them therein (nothing but) the heaving of sighs and sobs: They will dwell therein for all the time that the heavens and the earth endure, except as thy Lord willeth: for thy Lord is the (sure) accomplisher of what He planneth. And those who are blessed shall be in the Garden: They will dwell therein for all the time that the heavens and the earth endure, except as thy Lord willeth: a gift without break.—The Qur'an, 11:106–108
The modern mind has addressed the undesirability of immortality. Science fiction writer Isaac Asimov commented, "There is nothing frightening about an eternal dreamless sleep. Surely it is better than eternal torment in Hell and eternal boredom in Heaven."
Physical immortality has also been imagined as a form of eternal torment, as in Mary Shelley's short story "The Mortal Immortal", the protagonist of which witnesses everyone he cares about dying around him. Jorge Luis Borges explored the idea that life gets its meaning from death in the short story "The Immortal"; an entire society having achieved immortality, they found time becoming infinite, and so found no motivation for any action. In his book "Thursday's Fictions", and the stage and film adaptations of it, Richard James Allen tells the story of a woman named Thursday who tries to cheat the cycle of reincarnation to get a form of eternal life. At the end of this fantastical tale, her son, Wednesday, who has witnessed the havoc his mother's quest has caused, forgoes the opportunity for immortality when it is offered to him. Likewise, the novel Tuck Everlasting depicts immortality as "falling off the wheel of life" and is viewed as a curse as opposed to a blessing.
University of Cambridge philosopher Simon Blackburn, in his essay "Religion and Respect," writes, ". . . things do not gain meaning by going on for a very long time, or even forever. Indeed, they lose it. A piece of music, a conversation, even a glance of adoration or a moment of unity have their alloted time. Too much and they become boring. An infinity and they would be intolerable."
Although scientists state that radical life extension, delaying and stopping aging are achievable, there are still no international or national programs focused on stopping aging or on radical life extension. In 2012 in Russia, and then in the United States, Israel and the Netherlands, pro-immortality political parties were launched. They aimed to provide political support to anti-aging and radical life extension research and technologies and at the same time transition to the next step, radical life extension, life without aging, and finally, immortality and aim to make possible access to such technologies to most currently living people.
There are numerous symbols representing immortality. Pictured here is an Egyptian symbol of life that holds connotations of immortality when depicted in the hands of the gods and pharaohs who were seen as having control over the journey of life, the ankh (left). The Möbius strip in the shape of a trefoil knot is another symbol of immortality. Most symbolic representations of infinity or the life cycle are often used to represent immortality depending on the context they are placed in. Other examples include the Ouroboros, the Chinese fungus of longevity, the ten kanji, the phoenix, the peacock in Christianity, and the colors amaranth (in Western culture) and peach (in Chinese culture).
- List of life extension-related topics
- Consciousness after death (science)
- Crown of Immortality
- Dyson's eternal intelligence
- Electronic Immortality
- Elixir of life
- Eternal youth
- Immortal DNA strand hypothesis
- Immortalist Society
- Immortality Institute
- Immortality test
- Indefinite lifespan
- Internal alchemy
- Life extension
- List of people claimed to be immortal in myth and legend
- Methuselah Mouse Prize
- Molecular nanotechnology
- Negligible senescence
- Tipler's Omega Point
- Queen Mother of the West
- Rejuvenation (aging)
- Simulated reality
- Suspended animation
- Nikola Tesla
- Xian (Taoism)
- Marshall Fredericks (2003). "GCVM History and Mission". Greater Cleveland Veteran's Memorial, Inc. Retrieved 2009-01-14.
- Oxford English Dictionary "Immortality"
- Gilbert, Scott F. (2006). "Cheating Death: The Immortal Life Cycle of Turritopsis". Retrieved 2009-06-14.
- de Grey, Aubrey; Rae, Michael (September 2007). Ending Aging: The Rejuvenation Breakthroughs that Could Reverse Human Aging in Our Lifetime. New York, New York: St. Martin's Press. p. 416. ISBN 0-312-36706-6.
- Joel Garreau (October 31, 2007). "The Invincible Man". The Washington Post: C01.
- Porter, Roy (January 2005). "Flesh in the Age of Reason". Journal of the Royal Society of Medicine 98: 41–42.
- Kurzweil, Raymond (2005). The Singularity Is Near: When Humans Transcend Biology. Viking Adult. ISBN 0-670-03384-7.
- Hayflick, L (2007). "Biological Aging is No Longer an Unsolved Problem". Annals of the New York Academy of Sciences.
- Bernstein C, Bernstein H. (1991) Aging, Sex, and DNA Repair. Academic Press, San Diego. ISBN 0120928604 ISBN 978-0120928606
- "Classification of diseases functioning and disability".
- Walker, Peter (1991). International Search and Rescue Teams, A League Discussion Paper. Geneva: League of the Red Cross and Red Crescent Societies.
- Lin Kah Wai (18 April 2004). "Telomeres, Telomerase, and Tumorigenesis -- A Review". MedGenMed 6 (3): 19. PMC 1435592. PMID 15520642.
- Scott F. Gilbert (March 5, 2003). "Cheating Death: The Immortal Life Cycle of Turritopsis". Developmental Biology, 8th edition. Retrieved 2007-04-02.
- "'Immortal' jellyfish swarming across the world". London: Telegraph Media Group. January 30, 2009. Retrieved 2009-06-14.
- "Aging and Death in an Organism That Reproduces by Morphologically Symmetric Division".
- "Bacteria Death Reduces Human Hopes of Immortality". New Scientist magazine, issue 2485, page 19. February 5, 2005. Retrieved 2007-04-02.
- Gilberson, Lance, Zoology Lab Manual, 4th edition. Primis Custom Publishing. 1999.
- Clark, W.R. 1999. A Means to an End: The biological basis of aging and death. New York: Oxford University Press.  About telomeres and programmed cell death.
- Harrison's Principles of Internal Medicine, Ch. 69, Cancer cell biology and angiogenesis, Robert G. Fenton and Dan L. Longo, p. 454.
- Williams, G.C. 1957. Pleiotropy, natural selection and the evolution of senescence. Evolution, 11:398-411.  Paper in which Williams describes his theory of antagonistic pleiotropy.
- Kirkwood, T.B.L. 1977. Evolution of aging. Nature, 270: 301-304.  Origin of the disposable soma theory.
- "Resveratrol may increase life span". Phytochemicals.info. Retrieved 2010-11-04.
- ":: compound resveratrol may turn off a protein that guards cancer cells from cancer-fighting therapies". Wordpress.rudramani.com. 2009-07-13. Retrieved 2010-11-04.
- MacRae, Fiona (November 20, 2008). "Scientists are a step closer to creating 'elixir of life'". Daily Mail (London).
- Alleyne, Richard (November 20, 2008). "Scientists take a step closer to an elixir of youth". The Daily Telegraph (London). Retrieved May 5, 2010.
- Robert A. Freitas Jr., Microbivores: Artificial Mechanical Phagocytes using Digest and Discharge Protocol, self-published, 2001 
- Anders, Sandberg; Nick, Boström (2008). Whole Brain Emulation: A Roadmap. Technical Report #2008‐3. Future of Humanity Institute, Oxford University. Retrieved 5 April 2009. "The basic idea is to take a particular brain, scan its structure in detail, and construct a software model of it that is so faithful to the original that, when run on appropriate hardware, it will behave in essentially the same way as the original brain."
- Miconi T. Evolution and complexity: the double-edged sword. Artif Life. 2008 14(3:325-44
- "retrieved 23 October 2010". Elpistheory.info. Retrieved 2010-11-04.
- "retrieved 23 October 2010". Accelerationwatch.com. Retrieved 2010-11-04.
- Adler, Mortimer J., ed.; et al. (1952). The Great Ideas: A Syntopicon of Great Books of the Western World. Chicago: Encyclopædia Britannica. p. 788.
- Dag Øistein Endsjø. Greek Resurrection Beliefs and the Success of Christianity. New York: Palgrave Macmillan 2009:47-104.
- Dag Øistein Endsjø. Greek Resurrection Beliefs and the Success of Christianity. New York: Palgrave Macmillan 2009:54-64; 100.
- Majjhima Nikaya 2.265, Samyutta Nikaya 5.9 (PTS)
- Adler, Mortimer J., ed.; et al. (1952). The Great Ideas: A Syntopicon of Great Books of the Western World. Chicago: Encyclopædia Britannica. p. 784.
- Van Biema, David (February 7, 2008). "Christians Wrong About Heaven, Says Bishop ". Time. Retrieved May 5, 2010.
- Maharishi Mahesh Yogi on the Bhagavad-Gita, a New Translation and Commentary, Chapter 1-6. Penguin Books, 1969, pp 94-95 (v 15)
- "vallalar.org". vallalar.org. 2010-07-07. Retrieved 2010-11-04.
- Creel, Herrlee G. (1982). What is Taoism? : and other studies in Chinese cultural history. Chicago: University of Chicago Press. p. 17. ISBN 0226120473.
- Maspero, Henri. Translated by Frank A. Kierman, Jr. Taoism and Chinese Religion (University of Massachusetts Press, 1981), p. 211.
- Robinet, Isabelle. Taoism: Growth of a Religion (Stanford: Stanford University Press, 1997 [original French 1992]), p. 3–4.
- Translated by Legge, James. The Texts of Taoism. 1962, Dover Press. NY.
- Hoshang, Dr. Bhadha. http://tenets.zoroastrianism.com/topi33.html
- Allen, Richard James, "Thursday's Fictions", originally published by Five Islands Press, Wollongong, in 1999, republished online in 2011 at the Australian Poetry Library
- Scientists' Open Letter on Aging
- A Single-Issue Political Party for Longevity Science
- Wilson, Ralph F. "Peacock as an Ancient Christian Symbol of Eternal Life". Jesus Walk Bible Study Series. Retrieved January 18, 2011.
- Allen, Richard James (1999). Thursday's Fictions. Wollongong: Five Islands Press. ISBN 0-86418-596-0.
- Alexander, Brian (2003). Rapture: How Biotech Became the New Religion. Basic Books. ISBN 0-7382-0761-6.
- Bova, Ben (2000). Immortality: How Science Is Extending Your Life Span-and Changing the World. Avon: New York. ISBN 0-380-79318-0.
- Cave, Stephen (2012). Immortality: The Quest to Live Forever and How it Drives Civilization. Crown. ISBN 0-307-88491-0.
- Cullmann, Oscar (1955). Immortality of the Soul or Resurrection of the Dead?. Archived from the original on 2009-10-26.
- Endsjø, Dag Øistein (2009). Greek Resurrection Beliefs and the Success of Christianity. New York: Palgrave Macmillan. ISBN 0-230-61729-8.
- de Grey, Aubrey; Rae, Michael (September 2007). Ending Aging: The Rejuvenation Breakthroughs that Could Reverse Human Aging in Our Lifetime. New York, New York: St. Martin's Press. p. 416. ISBN 0-312-36706-6.
- Edwards, Paul (1997). Immortality. Prometheus Books. ISBN 1-57392-130-0.
- Elixxir (2001). The Immortalist Manifesto: Stay Young & Save the World. Authorhouse Books. ISBN 0-7596-5339-9.
- Freitas Jr., Robert A. (2002). "Death is an Outrage". Retrieved 2008-02-14.
- Hall, Stephen S. (2003). Merchants of Immortality: Chasing the Dream of Human Life Extension. Boston: Houghton Mifflin. ISBN 0-618-09524-1.
- Immortality Institute (2004). The Scientific Conquest Of Death. Libros En Red. ISBN 987-561-135-2.
- Perry, R. Michael (2000). Forever For All: Moral philosophy, Cryonics, and the Scientific Prospects for Immortality. New York: Universal Publishers: New York: Universal Publishers. ISBN 1-58112-724-3.
- Pickover, Clifford (2007). A Beginner's Guide to Immortality: Extraordinary People, Alien Brains, and Quantum Resurrection. New York: Thunder's Mouth Press. ISBN 1-56025-984-1.
- Rohde, Erwin (1925). Psyche: The Cult of Souls and Belief in Immortality among the Greeks. New York: Harper & Row.
- Salmond, Stewart (1903). The Christian Doctrine of Immortality.
- West, Michael D. (2003). The Immortal Cell: One Scientist's Quest to Solve the Mystery of Human Aging. Doubleday. ISBN 0-385-50928-6.
|Look up immortality in Wiktionary, the free dictionary.|
|Wikiquote has a collection of quotations related to: Immortality|
|Wikisource has the text of the 1920 Encyclopedia Americana article Immortality.|
- Scientists are Close to Finding a Way to be Immortal
- Turritopsis nutricula:Palscience Meet The Only Immortal Species on Planet Earth
- The Methuselah Foundation Aubrey de Grey's non-profit organization dedicated to finding a cure for aging
- KurzweilAI.net Ray Kurzweil resource site
- BiologicalGerontology.com Chris Smelick's Biogerontology site
- Vitae Institute Chris Smelick's non-profit organization
- ELPIs Theory Marios Kyriazis' theory of human biological immortality
- Immortality Institute Scientific and sociological discussions, activism, research
Religious and spiritual prospects for immortality
- "Death and Immortality" Dictionary of the History of Ideas, etext at the University of Virginia Library
- "Immortality" Immortality – What Will Eternal Life Be Like?
- The Immortality of the Soul and the Resurrection of the Body Lecture by Heinrich J. Vogel
- An Essay on the Scriptural Doctrine of Immortality by James Challis
- Eternity: Christ’s Return, Chiliasm, Resurrection of the Dead, Judgment, Hell, Luther on Eternity, Heaven J.P. Meyer, The Northwestern Lutheran, August 22, 1954, Vol. 41, # 17 to April 14, 1957, Vol. 44, #8
- "How you Can Have Eternal Life" Jack Graham, PowerPoint Ministries, Christianity.com
- Got Eternal Life? Got Questions Ministries
- Immortality Taoist essay, personaltao.com
- The Trial to Conquer Death Ancient Scientific Yoga – The First Atom's Final Attempt
-  A review by Dr. Peter Fenwick of the book Human Immortality by Mohammad Samir Hossain
- Mary Shelley's The Mortal Immortal