Here is part of an interesting article from:
http://www.trimberger.org/programs/obse ... redict.htm"OK, so you've observed something. How do you know it is right? How do you know you observed it correctly? Or wrote it down correctly? Or there wasn't something else happening that you didn't notice (like someone bumped the table or something) that messed up your observation? Why, you just do it again. This is the second important part of science: replication. Do it again. If we observe something, and we describe what we did and other people can repeat our experiment and observe the same result, then we can conclude we've correctly observed what is true.
This is a big deal and it is the reason why scientists don't care much about reports of ESP (Extra-Sensory Perception), mind reading and stuff like that. Not because they don't like the people doing it, not because the people doing it aren’t smart, not because they don’t use big words, but because other people are unable to repeat the experiment and get the same result. It's that simple. In science, if you can't replicate it, then you don't understand it. It isn't science. Accidents and coincidences happen all the time. Nobel Prize-winner Richard Feynman said science is what we have learned about how to keep from fooling ourselves."