Below is an answer I wrote for Quora. Original
Why is homeopathy generally considered quackery?
Among intelligent, reasonable people, homeopathy is considered quackery for a variety of reasons.
Let's start with the simple, obvious reasons.
- Because there is no plausible method for it to work. If homeopathy is true, we have to throw out vast amounts of what we know about chemistry and biology.
- Because the best evidence we have suggests it is bollocks: comprehensive and systematic meta-analyses of the best clinical evidence shows homeopathy doesn't do better than placebo. This is in spite of over 200 years of homeopathic practice: if you can't deliver the evidential goods after two centuries, it may be time to consider the case closed.
These two things alone should be enough. But once you look into it further, the wild levels of crazy give people much stronger reasons to reject homeopathy and consider it quackery.
- Because homeopaths use special pleading to weasel their way out of having to play by scientific rules. When people bring up the unfortunate little matter of how the meta-analyses of the clinical evidence points clearly towards it being bullshit, their response blames the process of randomized controlled clinical trials for not being "sensitive" enough to pick out the effects of homeopathy. On the odd occasion that a (usually small, usually shitty) clinical trial is positive for homeopathy, they trumpet it from the rooftops, but when the bulk of the clinical trial-derived evidence turns out to say homeopathy is bullshit, they complain about the best methodology we have. (Incidentally, the only reason we have yet to find evidence of ghosts is because of lack of properly attuned ghost detectors. The scientific method sucks, man.)
- Homeopaths argue from authority—no, wait, celebrity. Dana Ullman, for instance, has written a whole book on famous people that use homeopathy. Homeopaths seem to argue that homeopathy must work because the British Royal Family use it and so do various celebrities. Because apparently movie stars and Royals are a useful substitute for evidence.
- Fetishisation of the past. Lots of references to fancy sounding Latinate pomposity and the wisdom of Samuel Hahnemann. Now, sure, there's nothing wrong with a due respect for history. There is something wrong with not really appreciating that medicine may have moved on a bit since the 19th century, since we discovered, oh, the germ theory of disease, DNA, the structure of the brain, electron microscopy and much else.
- The method that homeopaths use to demonstrate amongst themselves that homeopathy works is epistemically flawed. A homeopathic "proving" was, historically, a damn sight better than what mainstream medics were doing in terms of testing. But they are subjective, not conducted with any blinding, and are basically not up to scratch in terms of an effective test of a medical claim. That homeopaths have failed to move their testing methodology forward as we discovered new statistical and scientific methods to prevent our own failure shows that they are dogmatically tied to nineteenth century writings rather than to actual science.
- The placebo industry is fucking huge. Boiron has a turnover of $313 million. Nelsons produce homeopathy for Tesco and Boots, two large UK retail chains. There's money to be made in sugar pills. But apparently, not enough that they'd be willing to actually plough some of their profits into doing some research...
- ...because homeopathy effectively segregates itself from the rest of medical practice. You can become a homeopath just by saying you are one, you can sell homeopathy without having to go through the rigorous procedures of testing and safety checking that pharmaceuticals go through.
- Homeopaths use distraction: instead of dealing with their evidential and scientific shortcomings, they are very quick to point the blame at others, usually 'Big Pharma'. Now, Big Pharma do a lot of bad things. But the reason we know about the bad things Big Pharma do is because they are held to a much higher standard than bullshit placebo pill peddlers. When Big Pharma fails, ideally regulators catch that. But there are no bloody regulators for homeopathy. "Big Pharma lies to patients" is a story precisely because we expect Big Pharma to not lie to patients. But as a society we have granted anyone who takes on the label "alternative" or "complementary" a get-out-of-responsibility-free card. You are as likely to see "homeopath lies to patients" in the newspapers as you are to see "virus discovered for Windows XP": it's just the cosy bargain that the alternative crowd have managed to secure.
- Homeopaths argue that their nonsense is justified because of failures by mainstream medicine to adhere to good evidence-based practice. Let us be clear: some mainstream medicine fails to adhere to good evidence-based practice. The answer is to demand that it starts to do so, but the conclusion doesn't follow. As the skeptical writer Guy Chapman writes, it's like saying "plane crashes are bad, so let's use flying carpets instead".
Homeopaths seem to think that the failure of some aspects of mainstream medicine to live up to its own evidence-based idealism justifies chucking the whole damn edifice of evidence-based medicine out and reverting to a barmy old system that we knew was bollocks back when Queen Victoria was alive.
- Despite the very questionable nature of homeopathy, homeopaths are making dangerous claims. If homeopathy was just reasonably healthy rich white people in Chelsea buying sugar pills to help with their interminable Google-induced hypochondria and/or vague, undefinable, unquantifiable feeling that something is wrong, I wouldn't give that much of a shit. Their money they are wasting.
But, no, homeopaths are actively threatening public health both in the West and in the developing world. 'Homeopaths Without Borders' is a non-profit that, following the Haitian earthquake, took up valuable space on flights to Haiti to distribute bullshit non-medicine when that space could have been used for actual doctors and volunteer first responders to bring actual aid that might have actually helped. In Africa and elsewhere, homeopaths are convincing AIDS sufferers that homeopathy is an 'alternative' to anti-retrovirals. When the best evidence science has to offer is "nuh uh, that doesn't work"... using it to treat life-threatening epidemics like HIV/AIDS is about as irresponsible as it gets.
- And finally... homeopaths seem to think that the only thing that makes people call them quacks is the science. No. Quackery runs far deeper than just science and evidence. Using political power to get the rules around medicine written in such a way that you are opted-out from having to do the same hard scientific work as actual doctors... that's quackery. Quackery is things like arguing that you are being persecuted by the "medical establishment", that anyone who thinks homeopathy is bullshit is a "paid shill of big pharma" (I'm still waiting for my cheque), and advocating the idea that "health freedom" is far more important than the protection of the public through regulation to make sure that the medicine you use is both safe and effective. All those social factors are what makes homeopathy pretty much the paradigm case of quackery.