I don't know if anyone remembers hearing about this back in September, but a team of scientists in Geneva ran an experiment that appeared to prove that neutrinos could travel faster than the speed of light.
Understandably, other scientists were skeptical - as they should be. See, ever since Einstein published his theory of special relativity, scientists have run experiments to test the theory - including attempts to find particles that travel faster than the speed of light. (Einstein claimed, if you recall, that nothing travels faster than light.)
Other scientists set about to try to reproduce the results from the Geneva group and.... failed. It appears that there might have been something wrong with the first experiment. I'm sure other groups of scientists will also attempt to replicate the initial results - or are in the process of doing so as I type.
This points out the difference between a scientific theory and a theory. A scientific theory has been tested and re-tested over and over and will continue to be tested as technology improves our ability to measure.
Even though Einstein's theory of special relativity is a pillar of the field of physics, scientists are willing to entertain the idea that it might be wrong and to try to prove it!
This is why I trust science so much and why we should seriously question those who tell us that science should not be taken seriously.
Image found here.