Introduce several famous pseudosciences in the world.

Alchemy is a thought and practice of chemical philosophy in the Middle Ages, and it is the embryonic form of contemporary chemistry. Its goal is to transform some basic metals into gold, find a panacea and prepare an elixir of life. Science now shows that this method is not feasible. But until the 19th century, alchemy had not been denied by scientific evidence. Some famous scientists, including Newton, have tried alchemy. The appearance of modern chemistry made people doubt the possibility of alchemy. [Transferred from the Iron Blood Community/]

First, alchemy in the West

Early alchemists lived from the first century to the fifth century. The earliest western alchemy works were written under the name of Democritus (about 1 AD). Western alchemy believes that metals are living organisms and gradually develop into perfect gold. This development can be promoted or imitated artificially. The means adopted is to isolate the form or soul of gold and turn it into base metal; In this way, the base metal will have the form or characteristics of gold. The soul or form of metal is regarded as a kind of aura, which is mainly manifested in the color of metal. Therefore, the plating of gold and silver on the surface of base metal is regarded as the transformation promoted by alchemists.

a fairly common method adopted by alchemists is to fuse four base metals, namely copper, tin, lead and iron, to obtain an alloy-like substance. Then the surface of this alloy is whitened, which gives it a silver aura or form. Then add a little gold to it as a seed or starter to turn all the alloys into gold. Finally, add another procedure, or etch away the base metal on the surface to leave a gold surface, or soak the alloy with sulfur water to make it look a bit like bronze, and the transformation is completed.

another idea widely spread by early alchemists is a more primitive idea, that is, metal is the product of sexual reproduction, and metal itself is divided into male and female. This concept plays an important role in Islam and medieval alchemy.

since the 12th century, the western countries where Christianity prevailed began to translate Arabic and Greek works, including alchemy documents. The influence of Greek alchemy on Europe is far less than that of systematic Arab alchemy. Refining gold is the main goal of European alchemy. European scholars have done a lot of experiments according to the theory of Islamic alchemy. Although it is impossible to succeed, it has accumulated a lot of knowledge for the development and emergence of chemistry.

second, Islamic alchemy [transferred from the iron and blood community/]

Islamic alchemy embodies a philosophy about essence, which is closely related to the philosophy of Hermes in ancient Greece, the alchemy of China, and the special principle of transforming minerals and metals into gold. In the history of Islam, Muslim scholars have long argued about the efficacy of alchemy. Orthodox religious scholars are mostly opposed to alchemy, while most natural scholars, although they don't believe that ordinary metals can be turned into gold, accept the basic view of alchemy. Ibn Sina, a famous Islamic physician, based his theory on the composition of metals on the theory of alchemy.

The earliest Muslim alchemist was Prince Khalid Ibn Yejid of Umayya. At the beginning of the 8th century, alchemy was very popular, and its representative was Jabir Ibn Khayan. His works "Seventy Books" and "The Book of Balance" are regarded as the basic theoretical works of Islamic alchemy and the most important documents about alchemy written in Arabic. Muslim doctor and alchemist Razi is known as the founder of developing alchemy into ancient chemistry.

Third, China's alchemy

Alchemy was called alchemy in ancient China.

after Qin Shihuang unified the six countries, China sent people to the sea to ask for immortal medicine. Emperor Wu himself was keen on immortals and elixirs. In the Eastern Han Dynasty, alchemy developed, and a famous alchemist, Wei Boyang, wrote the book "Zhouyi Shentongqi" to illustrate the theory of immortality. After that, Tao Hongjing, an alchemist in the Jin Dynasty, wrote True Letters Patent. In the Tang Dynasty, alchemy was combined with Taoism and entered its heyday. At this time, Sun Simiao, an alchemist, wrote The Secret of Dan Fang. These alchemy works have a lot of chemical knowledge. According to statistics, * * * has more than 6 kinds of chemical drugs, and there are many records about chemical changes.

Fourth, the influence [transferred from the Iron Blood Community/] alchemy has been proved wrong by modern science. However, as a pioneer of modern chemistry, it played a positive role in the history of chemical development. Through alchemy, people have accumulated experience in chemical operation, invented a variety of experimental instruments and learned a lot about natural minerals. Alchemy became the basis of the emergence and development of modern chemistry in Europe.