Argument: Medical advancements once feared are now accepted; cloning is the same
Nick Bostrom, Faculty of Philosophy at Oxford University. "Human Reproductive Cloning from the Perspective of the Future". December 27th, 2002 - "Historically, we find that many a great medical breakthrough, now rightly seen as a blessing, was in its own time condemned by bioconservative moralists. Such was the case with anesthesia during surgery and childbirth. People argued that it was unnatural and that it would weaken our moral fiber. Such was also the case with heart transplantations. How yucky to take a living heart out of one person and put it in the chest of another! And such was the case with in vitro fertilization. These "test tube babies" would be dehumanized and would be suffer grave psychological harm. Today, of course, anesthesia is taken for granted; heart transplantation is seen as one of medicine's glories; and the public approval rate of IVF is up from 15% in the early seventies to over 70% today.
I think we can learn something from these historical episodes. One lesson is that our immediate emotional reactions to medical developments are an unreliable indicator of their morality. We are prone to prejudice and to narrow-minded underestimatation of the long-term benefits of technological development. The "yuck factor" needs to be treated with a great deal of skepticism, and, pace Leon Kass, we should be wary of viewing it as embodying a great "Wisdom of Repugnance", especially for the purposes of making public policy.
[...]By the time the first human clone becomes an adult, the moral debates over cloning will probably be long forgotten. The present opponents of cloning may have retired or moved on to being outraged about other things. The clone will hopefully be descibed in more welcoming language than that used by many current commentators."
"The case for cloning humans". The Age. January 1, 2003 - "Whenever a new possibility comes along we tend to oppose it. IVF was opposed; surrogacy even more so. But we have come to accept both. In the case of IVF, there were similar fears about the risk of harm to the child - and we have come to live with the actual results. So it might be with cloning. What at first seems unthinkable might turn out to be a blessing for some or a possibility for many."