It is truly ironic that the only way persons become immortal is through their own mortality. Men and women of past are considered great because of what they did while they were alive: yet consider the thought experiment of what would happen to Caesar or Alexander or Einstein's reputation if they had never died. We would be able to say of them, "Yes they might have done those great things some many years ago, but what have they done since or what are they doing currently to merit such claim?"
Truly with new actors entering into the limelight for their own 15 minutes of fame, the deeds of those past would fall away to the deeds of those present. Then we could compare the living Einstein or living Caesar to the living heroes of today, choose your own candidates for comparison. In such an arena, of living competition, ever lasting -- immortal -- acclamation would surely be impossible. Therefore it is only because these men have died, that they are able to live on our tongues today, and for humans to come. This sets up the paradox that if one were truly immortal their names would eventually die: as what happens with "immortal" religions -- religions come and go, change, and are converted; while if people were mortal, their names could become -- in human terms -- truly immortal: never changing or being converted.
The position the deists, the theists, the supernaturalists: the religious hold to is not so different from this mortality-immortality paradox. Most would claim that their gods either have already lived and died, or rather can choose when to, physically, enter this world, and then at choice again depart -- making the Gods too both mortal and immortal. Always present in some form, yet not always present in ours.
Further, it is the will of every rational person to be, and not die; or rather put, to hold off death for as long as possible. The way humans have done this is by creating an idea of themselves with the aid of memory, in which they associate the very essence of their being with their actions of the past. This enables them to recall which actions produced life, or at least the actions which would enable them to run from death, and in so doing they hope to replicate those very actions so as to continue living, and hopefully a better life than before. It is therefore no surprise the phenomena which we call "good": such as saving a person's life, are also the phenomena which we like. Hence we can also say that it is a fundamental trait of humans to seek, to the degree most possible, their own immortality while knowing full well that they too shall surely die.
In the three preceding paragraphs I hope to have shown that people, the supernatural, and the notion of fame all derive their essence from this mortality-immortality paradox. Immortality is found in the non-mortal objects of adoration. Yet these objects of adoration only found their reputation due to the actions they undertook while mortal. Further, the only way people can be sure, while mortal, that they will become immortal is to make themselves immortal within their own lifetime. This is done by making ones' self as much like the supernatural as possible: powerful yet humble, smart yet cautious, kind yet feared, and most important: alive.
Yet in order to live as such requires that people come up with an idea of themselves. They then consult this idea of themselves before ever acting. This is the source of Freud's "Superego," Socrates's "Daemon" and Adam Smith's "Unseen Witness." We are the producer of this idea of ourselves, and we constantly watch our own actions. This idea is an effect of our mind, like how sight is the effect of the eye; and the two become so confused until we cannot tell the difference between us, and our own conception of ourselves. To some, this may be a problem. Worse, how can we move our hand or know what to say without thinking it? We believe this idea must have power over us, because it can have power over us. Yet those who struggle may find peace in knowing that this is only their mind's thought, and not their actual mind. Further, they make the jump from the possible to the inevitable without showing that multiple possible realities exists already from which one would eventually lead to an inevitability. One can never show that there is an a priori possibility. Because the source of any possibility is that it is possible with respect to something else: it is a relative conception. The problem is that one can never make consciousness relative, for doing so would only produce an effect of the mind, like a thought, and never the actual cause: the thinking mind itself. Yet, we still turn to this idea of ourselves for justification of our actions. This is what Bernard Williams calls "moral self-indulgence." Where we are moral, but only to further our idea of ourselves and not for the sake of other people.
To finally put the matter at rest, one must consider "how" a thought is produced, rather than just "what" the thought is. It is in the "creation" of ideas, realities, and histories that we find ourselves at the point of being both mortal and immortal. We have created something potentially immortal: a thought or action, and yet produced it in a mortal world. Again, this creation can never be explained. For explanations derive their justification from their content and not how that arrived at their content. They make a "must" out of an a posteriori, and then impose that 'must' upon what had to have come before it occurred. This is a ridiculous proposition and it is known as "the problem of induction." Thus in conclusion: the mortality-immortality paradox is solved when we show that even human existence: the essence of mortality, is unquantifiable. In so doing we are no longer mortal nor immortal, we are rather, free. Following, we no longer need our own "unseen witness," nor an imposed ideology. We become the creation of our own lives.