For one thing, the attributes of the alchemical or mythic immortal are often known by many names. These names have in some cases been translated as having alternately systemic, spiritual, personal, or ideological value. The tree of life known as the Sephiroth to the Hebrews may also be translated as the Derivellis, a tree of the permutations with some resemblance to the Net of Indra which reflects the many magnificent permutations of life. The secret of this device is as easily exceptionism, as the simple reality of manifestation, and any necessary associations one might have for the usefulness of experience.
Similarly, the dove device present in Christian religious motifs---including frequently stained glass windows---is also an ancient alchemical symbol used by alchemists to describe ambergris, the substance that was said to render the eater immortal. Especially in company of a cup, which can represent 'bounty' or 'psychology' alternately, as suggested by the Cups suit of Tarot used by Jews, the dove (or for the alchemists, traditionally the swan) might be marked with a Cross, which is part of the original alchemical symbol for ambergris: a device combining the swan and the cross.
It is interesting to note that a cross is one of the common symbols marked on a tree, used to symbolize the conjunction of lovers, or to make two people look like fools. If the conjunction with a woman is said to bring marriage and long life (expressed in the feminine symbol, which is similar to the Ankh), then this conjunction carving might represent a kind of figurative imbibing of ambergris, or alternately, in the case of fools, the danger said to be associated with digesting the substance.
The clear association in that case is also with the tree of the Sephiroth, and by extension Fortune and the Tower. These symbols are related to arbitrating the Fate of life, and hence the Fate of immortality. The tree carving, which appears popularly in Peter Pan, is also a sign of conjoining opposites such as Truth and Fable, Simplicity and Complexity, Macrocosm and Microcosm, and Specific and General. The figure of conjunction appears in alchemy as the Doppleganger or shape-shifter, the two-headed man, and the King and Queen or Sorcerer and Sorceress. The conjunction then becomes a symbol of the alchemical purification of thoughts or elements into philosophical gold, which can be linked to Buddhism. In Buddhist meditation, the process of discarding unnecessary thoughts leads to enlightenment and wisdom, called Nirvana.
It is an interesting point whether the Buddhist journey is all that is intended by the quest for immortality. Clearly, if that is not the case, then some have been fooled. Even if Buddhists will not admit that they are pursuing immortality, it is clear at least in the Mahayana tradition that Buddhas are immortals, that there are countless of them, and that the path leads there. I will leave off Buddhism as a metaphorical position, which is one actual stem or embodiment of what may be determined to be immortal. Perhaps Buddhists cope with the world, or perhaps they cope with immortality. It seems that from an ordinary point of view that this is indeterminate, for Buddhists, in this initial perspective, may be either enlightened or unenlightened. In either way, they may be Buddhists.
But what if religion is for the Gods? This would explain how the Christian trinity hold that there is only one-god-in-three, as though to say that the only God who is not God is the perspective of God, and as such, God is his own religion, besides being-actually-in-existence-somehow. Perhaps the culmination of some religious vantage points is that God has not yet been realized. This is in keeping with the current conventions about the pursuit of immortality. E.g. that it has not yet been a corporatized drug. If as physicists now claim, there are many vantages on the universe that are themselves immortal, but which are only realized from one angle, then this explains how God could seem emergent, rather than actual. Furthermore, if some of these perspectives could be realized by taking an immortality drug that is soon created, people would begin to believe that those perspectives always existed. They would believe that these perspectives, created by their own minds, were worthy of religion.
It is also possible that human imperfection goes a long way towards explaining the prospect of immortal life. Even ignoring a relative argument in which some form of immortality 'might not matter ultimately', it can be foreseen that human perspectives have a lot to do with the perceived reality of immortal life. They are the reality, aside from some 'obvious' factors which, collectively, may not always emerge even in the real case of an immortal being.
There are exceptions to the variablist view that immortality is a contingent case, which depends on examples and contexts of comparison. For example, someone may believe that the quest is foolish, or that fools are responsible for the failure to achieve some high-level psychological panacea. Or, someone may believe that God is one unified, utterly perfect being, who can only be achieved, if at all, in some form of singularity. I would argue that this last case is something like selling the soul of immortality. There is a case, in the context of my prior examples of four categories ending in adaptivity, for an adaptive view of immortality. Indeed, immortality if it is to exist, must be grounded not in some drugged-out semi-conditional 'prospectus' of reality (a dream in which nightmares are as real as functional conditions), but rather in the very urban, governmental, and role-playing environments which have been introduced as norms for functional people.
Returning to the first context of Systems, Spirituality, Personality, and Ideologues, and the second context of Tree, Cup, Bird, Cross there are numerous permutations which seem useful to the study of immortality.
For one thing, the tree seems like a system of government. Through the formalization of technology and support for modal existence and contingency, government may be a useful permanent symbol for immortal life, garbed in the appropriate justice of having helped people achieve that aim.
Secondly, chemistry and personality have become a quasi-permanent marriage via the institutionalization of drugs and the psychologization of personality and personality testing. People inevitably will be divided by personality and other data such as genetics and sexuality. This will be further influencing upon the structure of virtual reality environments ('The Metaverse') allowing partial realizations and experiments with what may otherwise seem like an exercise in patience.
Thirdly, the cross has become a kind of urban symbol which I associate with categorical knowledge (the Quadra, or Cartesian coordinate system, in relation to properties such as personalities or dualities), so there is an obvious integration of knowledge with society that has not always seemed possible. This carries over into the structuring of information, and hence the enhancement and overall integratedness of immortality and longevity.
Fourthly, the bird---a frequent symbol for the soul, said to have been raised by girls in noble families---and ideology, are inevitably combined. There is a new resurgence of the need for an Ideology of the Soul, as expressed in these prior conditions of psychology, personality, knowledge, and technology. It is pragmatically important that these sectors of reality, whether they are principles, or institutions, or just feelings being interpreted, are also encounters with the realm of chemical stimulation and information immersion. The overall prospect is very exciting, that is, when science leaps to meet up with the adequacy of imagination (for surely, we cannot rely on telepathy to find indicators of the permanence of the mind. At some point, life is a gift. And clearly, being as real as it is, the urban project for immortality is a good starting place).