Analyzing high-tech proposals for living indefinitely, University of Ghent bioethicist Francesca Minerva and researcher Adrian Rorheim identify two main paths that are currently pursued: constant physical rejuvenation and uploading one’s mind to a computer system.

They favor constant rejuvenation as “less problematic”:

Gerontologists such as Aubrey de Grey argue that growing old is a disease that we can circumvent by having our cells replaced or repaired at regular intervals. Practically speaking, this might mean that every few years, you would visit a rejuvenation clinic. Doctors would not only remove infected, cancerous or otherwise unhealthy cells, but also induce healthy ones to regenerate more effectively and remove accumulated waste products. This deep makeover would ‘turn back the clock’ on your body, leaving you physiologically younger than your actual age. You would, however, remain just as vulnerable to death from acute trauma – that is, from injury and poisoning, whether accidental or not – as you were before.

Francesca Minerva and Adrian Rorheim, “What are the ethical consequences of immortality technology?” at Aeon

But the rejuvenees, they warn, might become very anxious people, immortal but for mishaps or enemies. That is, most of us expect, more or less, to die sometime, preferably when we are old; we don’t literally think that we need not die at all if only we took more precautions.

Uploading one’s mind to a computer system is proposed by Ray Kurzweil, among others, who predicts that it will be available by 2045. The problem with that, Minerva and Rorheim note,

On the other hand, mind uploading would open up a plethora of completely new and unfamiliar ethical quandaries. Uploaded minds might constitute a radically new sphere of moral agency. For example, we often consider cognitive capacities to be relevant to an agent’s moral status (one reason that we attribute a higher moral status to humans than to mosquitoes). But it would be difficult to grasp the cognitive capacities of minds that can be enhanced by faster computers and communicate with each other at the speed of light, since this would make them incomparably smarter than the smartest biological human. As the economist Robin Hanson argued in The Age of Em (2016), we would therefore need to find fair ways of regulating the interactions between and within the old and new domains – that is, between humans and brain uploads, and between the uploads themselves. What’s more, the astonishingly rapid development of digital systems means that we might have very little time to decide how to implement even minimal regulations.

Francesca Minerva and Adrian Rorheim, “What are the ethical consequences of immortality technology?” at Aeon

This sounds like a roundabout way of saying that the uploaded minds might be seen as superhuman, even though, as Minerva and Rorheim observe, “it’s not clear whether you would survive in any meaningful sense if you were copied several times over.” If you didn’t, something that used to be you might exist and be cognitively superior to the common run of humanity but the “you-ness” is gone.

The authors also warn, “We can be pretty certain, for instance, that rejuvenation would widen the gap between the rich and poor, and would eventually force us to make decisive calls about resource use, whether to limit the rate of growth of the population, and so forth.”

Such considerations as limiting the “rate of growth” of the population may relate to a controversy in 2012 involving a paper written by Dr. Minerva and Dr. Alberto Giubilini:

Dr. Francesca Minerva, a research associate and ethicist at Oxford University, has been receiving death threats after co-writing an article arguing that killing newborns should be as permissible as getting an abortion.

The controversial article posited the idea that newborns and fetuses were only potential persons, lacking the same moral status and capabilities as actual persons like infants, young children and adults. Therefore, after-birth abortions should be permissible in all the cases where abortion is, including cases where the newborn is not disabled.

Melanie Jones, “Dr. Francesca Minerva: After-Birth Abortion Article Defended After Death Threats” at IBTimes (March 2, 2012)

Dr. Minerva has since clarified that that paper was a “pure academic discussion,” an exercise not meant to be shared outside the academic community.

Further reading on whether mind-uploading is on the horizon and what it would mean:

Tech pioneer Ray Kurzweil: We Will Merge with Computers by 2045. For computers, “Even the very best human is just another notch to pass,” he told the COSM Technology Summit. Advocates point to the success of Kurzweil’s past predictions as evidence that his Singularity is indeed Near, as his 2005 book predicts or Nearer, as his forthcoming one (June 2020) does. But questions bubbled to the surface.

Attend your own funeral! It’s easy if you upload your consciousness to the cloud, says futurist.

Claim: Yes, you can upload your brain. Fine print: They might have to kill you first.

and

Can we cheat death by uploading ourselves as virtual AI entities? Transhumanism is a curious blip in a science and technology culture in which it is otherwise axiomatic that humans are merely evolved animals.