In 1818, the 21-year-old Mary Shelley published the great (perhaps greatest) classic of gothic literature, Frankenstein, Or the Modern Prometheus. As we all know, it's the story of a brilliant and anguished doctor who wants to use the cutting-edge science of his time — the relationship between electricity and muscular motion — to bring the dead back to life. Two decades before Shelley's novel, the Italian Luigi Galvani had shown that electric pulses could make dead muscles twitch. He even had a demonstration of frogs hanging from a metal wire that danced like crazy during an electric storm. It must have been quite a sight.
If life is movement, and if electricity can cause muscles to move, why not bring the two together to try and resuscitate the dead through science? Would man then be like God?
We all know how the story ends, in tragedy. As Adam wanted Eve, the "creature" demands a female companion so that he can live in isolation — but not in loneliness — from the rest of humanity. Horrified, Dr. Frankenstein refuses. He doesn't want to create a race of monsters capable of threatening the future of our species.
The novel examines the ethical boundaries of science: should scientists have complete freedom to pursue their research? Are there certain themes that are taboo, that must thus be censored? If there are such taboo themes, who decides what they are? What limits should be imposed on the scientists? And who imposes them?
These are big, complex questions that go to the heart of ethics and science.
For example, should we treat old age as a disease? If so, and assuming we arrive at a "cure," or at least a substantial increase in lifespan, who would have the right to benefit from it? If the "cure" is expensive, and it most certainly would be at the outset, only a small fraction of society would have access to it. In this case, society would be artificially split, where those who can would live much longer than those who can't. (To a certain extent this happens already, as the poor in many countries have much shorter lifespans than those in developed countries. In this hypothetical, the problem would only be exacerbated.)
And how would we deal with loss? If some live much longer than others, the ones that do would see many pass away. Is this an improvement in their quality of life? Only, it seems, if extended longevity were evenly distributed among the population and not the privileged of a few.
With this in mind, having universal access to medical care, as in Obamacare, should be a force toward equalization. We would all have access to the same high quality care. And to an increased quality of life and lifespan.
Another example is in the area of human cloning. What would the purpose be? If a couple can't have kids, there are many options already available, including adoption. On the other hand, human cloning may become part of the extended longevity program: imagine if our bodies and memories could be reproduced indefinitely. In this case, a person would persist in existence for a very long time indeed. This is sci-fi now, but not something that the laws of nature seem to forbid a priori.
Of course, we can't clone humans now and we have no clue how to transport memories from brain to brain. But to say "never" in science is very risky. We are inching that way.
The initial impulse we have in cases like these is to forbid this or that, make sure a particular kind of science never gets done. We live in fear of opening Pandora's Box. But this approach is na´ve at best.
If it's not done here, it will be done elsewhere, for good or evil. Here is the essential point: it is not science that is good or evil; we are the ones creating good and evil through the choices we make.