When we say that something is scientific, we tend to imply that it is authentic, clear and secure. Therefore, all want their area to be treated as scientific knowledge. Other fields of study are classified as pseudo-ciencientificos or false science, whose practitioners describe their scientific activities and even use the language of science. But how can we separate the scientific from what is not? No easy task. Define the boundaries of science would be a job without exito1.
The frontier between the science of pseudo-science is defined by the demarcation criterion used. This has been discussed by many scientists and philosophers of science of the twentieth century. Kant stated that the trials are all science must be synthetic a priori. Synthetic because they have to be extensive, ie, our knowledge of science is to be extended. And a priori because their truth can not rely on the experience, which is particular and not universal in this way are also needed.
This is an example of a criterion of demarcation. As such deprive others of being called scientific knowledge. Another criterion of demarcation would be that established the Circle of Vienna: scientist only what is empirically verifiable. That which can not be proved by experience is neither true nor false, meaningless, is not scientific. Popper was critical of the Vienna Circle. His criterion of demarcation was based on falsifiability. This states that continuously check a theory does not serve to prove its validity because there may be an object that has not been subjected to analysis and to disprove that theory.