The history of pseudoscience is the study of pseudoscientific theories over time. A pseudoscience is a set of ideas that presents itself as science, while it does not meet the criteria to properly be called such.

Distinguishing between proper science and pseudoscience is sometimes difficult. One popular proposal for demarcation between the two is the falsification criterion, most notably contributed to by the philosopher Karl Popper. In the history of pseudoscience it can be especially hard to separate the two, because some sciences developed from pseudosciences. An example of this is the science chemistry, which traces its origins from the protoscience of alchemy.

The vast diversity in pseudosciences further complicates the history of pseudoscience. Some pseudosciences originated in the pre-scientific era, such as astrology and acupuncture. Others developed as part of an ideology, such as Lysenkoism, or as a response to perceived threats to an ideology. An example of this is creationism, which was developed as a response to the scientific theory of evolution.

Despite failing to meet proper scientific standards, many pseudosciences survive. This is usually due to a persistent core of devotees who refuse to accept scientific criticism of their beliefs, or due to popular misconceptions. Sheer popularity is also a factor, as is attested by astrology which remains popular despite being rejected by a large majority of scientists.

 

Note:   The above text is excerpted from the Wikipedia article History of pseudoscience, which has been released under the GNU Free Documentation License.