The term
pseudo-science gets kicked around a lot when discussing whether an idea, report, or even a whole field is really scientifically valid or viable.
It is most often hurled as a derogatory term in the heat of debate. It is also, but less often, used as a useful disctinction.
There is one thing I see a lot of people forgetting, though:
The distinction between pseudo-science and science is one of approach and method, NOT of subject matter.
It is possible to study (or at least attempt to study) anything scientifically, as long as you use a scientific approach. As well, it is possible to approach anything pseudo-scientifically, as long as you use pseudo-scientific approaches.
Examples:
Many areas of parapsychology are treated as inherently pseudo-scientific. This is as nonsensical as saying that Boston is fast, simply because I drove quickly to get there. I could just as easily drive more slowly. Take ESP for instance. It is possible to use unscientific or pseudo scientific methods to "prove" the existence of ESP. It is also possible to investigate it scientifically. This has been done, with very interesting results. (see ESP for more information).
Conversely, many areas of subject matter that are considered "scientific" are often investigated pseudo-scientifically. Take medicine. Companies with special interests in public opionion have commissioned the most absurd pseudo-scientific reports, and used data pseudo-scientifically. Cigarettes are a good example -- many pseudo-scientific studies and reports were generated to show that cigarettes were "safe".