Homeopathy may be the most controversial but also the most popular alternative medicine. While some argue against it, others swear by its great power and effectiveness. How does homeopathy work? How did it become what it is today, and what can modern medicine learn from it? The first principle of homeopathy is "like cures like." Remedies use ingredients that cause the symptoms you want to cure. In practice, that means that remedies against fever could, for example, be made from belladonna, which also causes fever. A mixture based from bee venom is used to treat itchy swellings, and so on. The second principle is the special method of preparation called potentization. The idea is that diluting and agitating the ingredients activates their curative powers and enhances their effect. To do this, the ingredient is dissolved in alcohol or distilled water. Homeopaths take one part of the solution and mix it with nine parts of water, diluting it down to one tenth of its original concentration, and shaking it. What you have now is a 1X potency: one-part ingredient and nine parts solvent, named after the Roman numeral X, for 10. Now, this process is repeated. Take one part, mix it with nine parts of pure water and shake it vigorously. Now you have 2X. You do this again and again until you reach the desired grade of potency. The finished remedy is then taken orally, or sometimes it's applied as little sugar pellets that are sold as globuli. A 20X potency, for example, is like dissolving one aspirin pill in the water volume of the whole Atlantic. But many are much more extreme, like 30C, for example. C means that the mixture has one part ingredient and 99 parts water. So the commonly sold 30C mixture means one part ingredient and one million billion billion billion billion billion BILLION parts of water. If we wanted a globuli pill with a single atom of the original ingredient, then our pill would be the diameter of the distance between the Earth and the Sun. 150,000,000 kilometers A pill so massive, that it would collapse into a black hole under its own mass. Because of this, potentization is one of the biggest criticisms of homeopathy. The extreme dilution is supposed to make the ingredients more potent, but on a physical level, this doesn't really make sense. Most homeopathic remedies are diluted so much that not a single atom of the active ingredient is left in them. The explanation of why the mixtures still work is that shaking the mixture after every dilution leaves behind a spirit-like essence of the ingredient. Basically, the idea is that water remembers what was put into it. But if this were true, then every substance that ever met a drop of water would leave an essence behind and lead to unpredictable effects when it was accidentally ingested. Think of all the stuff that lives and floats in the oceans. Every sip of water would be a supercharged homeopathic cocktail. So how did homeopathy become the most successful alternative medicine? In the 18th century, medicine was very different from today. Treatments like bloodletting left the patient worse off than before. So German physician Samuel Hahnemann wanted a non-invasive, natural way of healing and developed homeopathy. And, in fact, homeopathic hospitals were soon successful because doing no harm beats doing harm. Hahnemann imposed very strict rules on his patients. First you had to avoid coffee, tea, alcohol, spicy food, sweet food. No old cheese, no onions, no meat. No clothes made from sheep's wool, but also no sedentary work, no sitting inside in stuffy air, no warm rooms, no riding horses, no napping, no playing games, no masturbation, and of course, no reading pornographic texts, and many more. Then, and only then, would his remedies work, according to the inventor of homeopathy. Of course, all of these instructions are ignored and not talked about today. Medicine has changed a lot in the last 150 years. Never before in human history have we enjoyed a comparable level of health. Never have we lived as long, and this is largely due to the new tools we've developed. Modern diagnostics, double-blinded studies, and scientific evaluation to check and prove which stuff works. Thanks to these tools, after countless studies and reviews, we know beyond a shadow of a doubt that homeopathy does not have any effect beyond placebo. But even so, who cares why it works if it helps people? Maybe you tried it and felt better, or you know someone that got over a horrible disease while using homeopathic remedies, and there are plenty of reports of it working for children and animals. What do we make of these experiences? The Placebo Effect is very real and not imaginary. No matter how smart you are, you're not immune to it. If people believe that something will help them feel better, their trust alone has the desired effect. And it's been proven that the Placebo Effect can be transferred. Children and animals rely on their parents or keepers and are in tune to their emotions. If a parent has a lot of trust in a treatment and eases up, this can help a child relax and help relieve symptoms. This could also be observed with animals who react strongly to the body language cues of the people caring for them. But the most powerful tool of homeopathy is time. Our bodies are survival machines. Infections pass on their own after a few days. But if you take some remedy when you already feel sick, and then start getting better, it feels like it did indeed cure you, when actually, it would have happened anyway. The homeopathy industry likes to play the gentle alternative to Big Pharma. But the homeopathic industry IS Big Pharma. Billions of dollars are made with extreme profit margins. The homeopathy industry has its own lobby organizations and fights its enemies as hard as it can. A lot of money is on the line. Globally, the market is expected to reach over 17 billion by 2024. Some critics even argue that the homeopathic industry is bad for public health because it creates distrust in proven medicine. The belief in homeopathy correlates with skepticism about vaccinations. This can discourage people to seek the help they need when their lives or the lives of their children are on the line. But there is actually a key to the success of homeopathy that we could, and should, copy. The first consultation with a homeopath can take hours and is very personal. For a patient who's already been on a pilgrimage from doctor to doctor, this level of attention and empathy can make a huge difference to their well-being, even if the conversation was not the point of the therapy. Modern medicine is efficient. It saves millions of lives each year. But it's also a strictly organized system. Tight budgets force doctors and nurses to deal with lots of patients. Consultations need to be time-efficient, diagnoses made quickly, treatments fast, which can leave patients feeling invisible, scared, and left behind. This is what modern medicine can learn from homeopathy. It meets a human need that has been left unfulfilled. We need to make time for the individual again. See people, not numbers. But as important as empathy is, it's not a substitute for actual treatment. Faith can move mountains, but sugar water can't cure cancer. After a short break of a few years, Kurzgesagt is back in German. Thanks to the support of Funk, we have relaunched the German channel and are beginning to upload a video every 1-2 weeks. Besides redoing our favorite videos, there'll be a number of videos that will not exist in English for a while. Check out the channel here, tell us what you think, and subscribe and watch a few. If the channel goes well, the German videos might become a regular thing for years, and we might even do more languages.