Grand Challenges Towards Achieving Immortality
Scientists and technologists aspire to achieve immortalities of different types using completely different theoretical groundings and technologies. Each approach poses different conceptual challenges.
2.5.1 Challenge #1: Decelerate or Stop Biological Aging
Scientists work on many different paths to decelerate or completely end the process of biological aging. To begin with, we use different definitions for aging, which of course impose different points of intervention. These, in turn, have different effects on the need to reconsider relevant concepts. For example, if aging and cell death are pre-programmed, then breaking that code opens up questions about whether someone placed that code there for a reason and whether breaking that code brings us close to that creator. By contrast, if aging is simply a process of metabolic and cellular burnout and overuse, we may not need to reconsider any concepts. Moreover, if we view aging as a multidimensional process of physical, psychological, and social change, then all of these changes need to be taken into consideration when talking about aging. For example, according to Kyriazis (Kyriazis 2003, 2005), chaos theory and entropy imply that more information will lead to more intellectual complexity, as well as more biological redundancy, i.e., less risk of aging and death.
2.5.2 Challenge #2: Replace Biological with Manufactured Tissues
This has already begun, with heart pacemakers, metallic joints, bionic limbs, eye and ear transplants, etc. Research also goes one step further in enhancing human capabilities by using technologies that are not necessarily designed as human homomorphs, as in the case of exoskeletons. Are emerging cyborgs or, eventually, robots still human? Should we draw a line or accept, as Minsky (Minsky 2004) suggested, “robots will inherit the earth, but they will be our children”?
2.5.3 Challenge #3: Regenerative Medicine
A term attributed to William Haseltine (founder of Human Genome Sciences; (Viola et al. 2003)), regenerative medicine refers to the “process of replacing or regenerating human cells, tissues, or organs to restore or establish normal function” (Mason and Dunnill 2008). The theoretical and technological approaches range from attempts to regenerate damaged tissues and organs in the body and/or stimulating the body's own repair mechanisms to heal previously irreparable tissues or organs, to replacing damaged tissue or organs either by growing (manufacturing) them in the lab using scaffolding technologies or “printing” (see also below) them layer by layer.
Repairing the Body from Inside At first glance, the idea that nanorobots inside our body will repair whatever needs to be repaired does not affect our concepts of life, human, or identity. What, however, if these robots are controlled from outside? What about the concept of free will, for example?
Manufacturing Organs Organs are engineered using decellularizing a living organ (removing cells to leave a clean extracellular structure) to keep only the skeleton. Stem cells are grown within the structure and re-create the organ. Artificially created structures are also being used as scaffolds to engineer, for example, heart valves or bladders. Three-D organ printers are also no longer science fiction. For example, Anthony Atala at the Wake Forest Institute for Regenerative Medicine (see, for example, (Nakamura et al. 2005; Xu et al. 2009)) has been trying to print heart valves, kidneys, livers, and other tissues using a technology analogous to inkjet printers, injecting human cells instead of nano-sized droplets of ink. The idea of manufacturing or “printing” human organs to replace those aging or malfunctioning opens up new conceptual challenges with regard to what it means for an organ to be alive, the constancy of the identity of the recipient, and even the mind-body question. What's more, the idea that someday we might develop printers that “print” printers (i.e., reproduction) challenges the very concept of life.
2.5.4 Challenge #4: Transfer the Mind to a Machine
This usually refers to the process of transferring or copying a conscious mind from a brain to a non-biological substrate. Even though still considered by many as farfetched science fiction, in some ways it has already begun. In the not-too-distant future, digital agents may represent us to some extent, behaving and acting like us. With the added functionality of learning from their mistakes, they will have a life of their own. Thus, a rudimentary self will continue to live in cyberspace even after our death. Once we have reached the point when an entirely, conscious self can be transferred, we will have managed to transfer the human mind to a machine. At that point, we will face new questions, such as, what happens if the biological equivalent continues to live?