(Do you have the link to the specific news article, kelly?)
I’m not exactly sure what you mean by “advance the human state,” kelly, but it looks like the sort of thing that I’m advocating. As for organ replacement, which I presume the lab-grown rat hearts are supposed to help us learn about, I doubt advances in medicine will deteriorate human well-being. Even better if new organs are created that function better than the human norm.
I am aware of the main objection to organ replacement, which is that people will all of a sudden stop taking care of the organs they already have because they can just replace them, because we all know people follow cartoon logic. We treat products as disposable only when they become really inexpensive, like paper. Even if livers become as affordable as PDAs, even if the organ recipients become stupid for the sake of dramatic necessity, who are the innocents that are harmed?