Pseudoscience is differentiated from science because – although it usually claims to be science – pseudoscience does not adhere to scientific standards, such as the scientific method, falsifiability of claims, and Mertonian norms.
Scientific method
Main article: Scientific method
The scientific method is a continuous cycle of observation, questioning, hypothesis, experimentation, analysis and conclusion.
A number of basic principles are accepted by scientists as standards for determining whether a body of knowledge, method, or practice is scientific. Experimental results should be reproducible and verified by other researchers.[24] These principles are intended to ensure experiments can be reproduced measurably given the same conditions, allowing further investigation to determine whether a hypothesis or theory related to given phenomena is valid and reliable. Standards require the scientific method to be applied throughout, and bias to be controlled for or eliminated through randomization, fair sampling procedures, blinding of studies, and other methods. All gathered data, including the experimental or environmental conditions, are expected to be documented for scrutiny and made available for peer review, allowing further experiments or studies to be conducted to confirm or falsify results. Statistical quantification of significance, confidence, and error[25] are also important tools for the scientific method.
Falsifiability
Main article: Falsifiability
During the mid-20th century, the philosopher Karl Popper emphasized the criterion of falsifiability to distinguish science from nonscience.[26] Statements, hypotheses, or theories have falsifiability or refutability if there is the inherent possibility that they can be proven false, that is, if it is possible to conceive of an observation or an argument that negates them. Popper used astrology and psychoanalysis as examples of pseudoscience and Einstein's theory of relativity as an example of science. He subdivided nonscience into philosophical, mathematical, mythological, religious and metaphysical formulations on one hand, and pseudoscientific formulations on the other.[27]
Another example which shows the distinct need for a claim to be falsifiable was stated in Carl Sagan's publication The Demon-Haunted World when he discusses an invisible dragon that he has in his garage. The point is made that there is no physical test to refute the claim of the presence of this dragon. Whatever test one thinks can be devised, there is a reason why it does not apply to the invisible dragon, so one can never prove that the initial claim is wrong. Sagan concludes; "Now, what's the difference between an invisible, incorporeal, floating dragon who spits heatless fire and no dragon at all?". He states that "your inability to invalidate my hypothesis is not at all the same thing as proving it true",[28] once again explaining that even if such a claim were true, it would be outside the realm of scientific inquiry.
Mertonian norms
Main article: Mertonian norms
During 1942, Robert K. Merton identified a set of five "norms" which characterize real science. If any of the norms were violated, Merton considered the enterprise to be nonscience. These are not broadly accepted by the scientific community. His norms were:
Originality: The tests and research done must present something new to the scientific community.
Detachment: The scientists' reasons for practicing this science must be simply for the expansion of their knowledge. The scientists should not have personal reasons to expect certain results.
Universality: No person should be able to more easily obtain the information of a test than another person. Social class, religion, ethnicity, or any other personal factors should not be factors in someone's ability to receive or perform a type of science.
Skepticism: Scientific facts must not be based on faith. One should always question every case and argument and constantly check for errors or invalid claims.
Public accessibility: Any scientific knowledge one obtains should be made available to everyone. The results of any research should be published and shared with the scientific community.[29]
Refusal to acknowledge problems
In 1978, Paul Thagard proposed that pseudoscience is primarily distinguishable from science when it is less progressive than alternative theories over a long period of time, and its proponents fail to acknowledge or address problems with the theory.[30] In 1983, Mario Bunge suggested the categories of "belief fields" and "research fields" to help distinguish between pseudoscience and science, where the former is primarily personal and subjective and the latter involves a certain systematic method.[31] The 2018 book about scientific skepticism by Steven Novella, et al. The Skeptics' Guide to the Universe lists hostility to criticism as one of the major features of pseudoscience.[32]