a feeding tube is not a "man-made machine."
Really? Where in nature does one go to find one? Do they grow them in your state? Does one just grow a tube out of their stomach when they can't feed themselves any more? Oh, you mean someone has to inject an artificially produced formula into the mass-produced feeding tube? It can also be administered by machine, with set dosings every so many hours or minutes. If you want to argue that a feeding tube is natural by any stretch of the imagination you're going to lose.