Therapies from nature sometimes work, but diluted dog rabies does not.
Some herbal remedies, including willow bark (second from the right), actually do work. But most don't.
Willow bark has a long and storied history. The Sumerians used it 4,000 years ago to treat pains of all kinds. So did the Egyptians after them, and the Chinese and the Greeks, but it wasn't until the turn of the 20th century that anyone bothered to isolate the active ingredient and begin manufacturing it into the pills we know it as today: aspirin.
We didn't even really understand the mechanism by which aspirin works as an anti-inflammatory until 1971, and yet for thousands of years humans have been treating themselves with it.
In some ways, this sounds like a triumph of natural medicine. The humble willow tree contained one of the best pain relief drugs we have, and those silly Westernized doctors just had to pay attention to what naturopaths had been preaching for eons. In reality, though, it exemplifies an old adage: What do you call alternative medicine that works? Medicine.
Plenty of our medicines originally came from plants—we still look to them today for potential new drugs. And that means that sometimes natural remedies do work. Foxglove plants really can treat heart failure because they contain digitalis. Cinchona bark and artemisia actually treat and prevent malaria because both contain quinine. Oranges could prevent scurvy because they're full of vitamin C.
Many of these naturopathic cures originated in times when we couldn't run clinical trials or investigate active ingredients. Once we started doing so, those natural medicines that worked were commandeered under a new umbrella: medicine.
This is why nearly all naturopathy is benign at best today—often those plants that really do cure diseases go into drug development and come out the other side as pills and tablets and gels. There are certainly a few remedies that do work, especially for minor ailments like joint or muscle pain, since pharmaceutical companies aren't necessarily interested in putting down millions of dollars just to develop another aspirin-esque drug.
But let's be clear about one thing: natural remedies and homeopathy aren't the same thing. Naturopathy, while not scientifically proven, is mostly based around using plants to treat diseases. Some of those remedies work, and on principle we can't dismiss a treatment simply because it comes from nature.
However, we can certainly dismiss all of homeopathy. And we will.