What is science, what is non-science and what is pseudoscience?

According to the characteristics of science, the main difference between science and non-science lies in its "positivity", that is, a theory that can be confirmed or falsified by facts, experiments or rational deduction is science. For example, some people say that this proposition cannot be confirmed or falsified after death, so it is not science. Similar theories about ghosts and gods, fate, feng shui, numerology, constellations, etc. are not science, nor are they the objects of scientific research.

However, just because it is not science, it must be wrong. Science has limitations. It only studies those propositions that can be verified or falsified. The spirit of science is not to easily prove a thing, nor to easily deny it. Confirmation needs to be confirmed, and negation needs to be falsified. For those contents that cannot be proved or falsified, science does not draw any conclusions, but only thinks that this is not the scope of scientific research, such as "God" or "the afterlife".