Bill McKibben‘s book Enough is a plea for reasoned debate over the impacts of genetic engineering, arguing that there is a line in the sand that we will be better off choosing not to cross. Essentially his argument is that a ‘genetically engineered’ human (say, someone whose embryo was tinkered with to make them smarter or more atheletic) will no longer find the same meaning in life that humans have experienced to this point. And at some point we may find that we’ve created a separate, enhanced, species that has little to do with humanity.
In the details, he argues that standard medicine and other non-genetic techniques can solve many of the medical issues that are used to argue for germline technology (for instance, the ability to test for certain debilitating diseases at an early stage). He feels that somatic gene therapy, which acts on a single individual, does not threated human meaning, but that germline activity (changing the DNA that will be inherited) is over the line. Not to mention human cloning!
McKibben makes a strong argument against the ‘techno-zealots’ like Rodney Brooks, Hans Moravec and others who claim that all genetic work is ‘inevitable’ – saying that they are simply interested in shutting down all debate.
I am a bit skeptical about the ability to make changes to DNA to make a person grow up to be ‘smarter’ (since I doubt we can define what this means), but I am sympathetic to McKibben’s argument. I do think there are some critical thresholds that we are approaching, and the social impact is massively important. I’d recommend Enough as a way to think about these issues. The books feels just a little dashed off, but I’d say that reflects the up-to-the-minute nature of the issues.