There is an urgency attached to mortality that would not be present in something or someone immortal. That is why, in my opinion, value is derived from life and mortality. Even the smallest things we do for enjoyment or for adding value to our life, while it may be inconsequential to the act of physically surviving, is something that holds value as we may never have the opportunity to do it again.
I would surmise an immortal would have no sense of urgency or drive to accomplish anything. What would it matter? Forever is a long time to try to keep one’s self entertained and fulfilled.
Why are shopping sprees exciting? You only have a short time to grab as much as you can. Now imagine a shopping spree that never ends, no time limit.
Imagine a bungie jump where the bungie never stops and theres no ground to rush up to you, just a space that goes on forever.
It is the finite that makes things interesting, that makes things valuable and worth keeping or trading.
My humble ramblings…
VES
Superman could still desire Lois Lane and the pursuit of a Romantic relationship, even if he knew he would live forever; the alternative then would be an eternity with a value or an eternity without it. I think it is apparent that some values are not dismissed merely by the absence of a ticking clock; Superman could still enjoy eating hamburgers because they taste good and provide him with comfort, even if he didn’t need them to live. That taste buds are ostensibly the product of natural selection and a guide to “survival” is not what is essential or relevant; that it brings him comfort and satisfaction, in terms of a pleasurable taste and texture, is, even if “survival” in the absolute sense is not a concern for him.
Whatever the basis for our desires, they can be destructive or beneficial; thus our passions must be tempered by a rational mind in order to determine what actions will truly be to our benefit. Thus, it is the capacity for happiness that determines the potentiality for the pursuit of values, not simply death. Mortality may provide urgency to those values, but they are not the source of values.
Even if one could scientifically extrapolate the link between mortality, natural selection, and desires, such a discovery would be a physiological one, and philosophically inconsequential.
To paraphrase Andrew Lewis (from when he was on the Radio): " I don’t even need to know why I want to eat the candy bar, I can simply look at the result that the consumption of the candy bar has on my life and make the decision."
Thus, if a being is rational, it must take into account all other facets of its nature and come to a determination as to what it must pursue for its long term well-being. If the robot has been programmed with feelings, or lets say it has the brain of a man but it is still immortal and invincible, it can still pursue values, so long as it has the capacity for happiness. Its means can only be determined by introspection and scientific study, but that it can is irrefutable if one is adhering to Rand’s definition.
After all, what would be the purpose of living for a rational being if it did not have the capacity for happiness? Such an animal would be the Houyhnhnms of Gulliver’s Travels, pursuing reason for reasons sake.
In short: It is the possibility of a positive and a negative in any action, and the faculty of volition that necessitates purposeful action, that gives rise to values; not simply “death”.