The webcomic xkcd is so often just absolutely brilliant.  The latest entry, The Economic Argument, pokes fun at a number of pseudosciences.  Take a look:

The point being made here is straightforward.  If those phenomena we typically categorize as pseudosciences (the first nine items listed) actually worked then somebody, somewhere would have put them to use on a daily basis and would be making money in the process.  But they don’t work!  One of the best sayings I’ve heard is, “If alternative medicine worked, then we would just call it medicine.”

So how is it that we judge a phenomenon as being either scientific or not?  We apply the scientific method.  If, like relativity and quantum electrodynamics, something is scientific then the theory can be used to make testable predictions and to produced repeatable results.  In other words, we could use scientific theories to make money if those reproducible results are beneficial to society.  Pseudoscientific ideas, on the other hand, do not produce guaranteed repeatable results.  Because they can’t, these theories (if we could even call them theories) are not useful for making progress or money based on their results.  Unfortunately these pseudoscientific claims are still used a means for scammers to dupe innocent people—that do not understand the scientific method—out of their money.