The power of science doesn't come from scientists being smarter than everyone else — it comes from a method designed to catch their mistakes. The core move is falsifiability: a scientific claim must make predictions that could, in principle, be shown false by observation. 'All swans are white' is scientific because a single black swan disproves it; 'invisible undetectable fairies cause gravity' is not, because nothing could ever refute it.
This inverts normal human reasoning. People naturally seek evidence that confirms what they already believe (confirmation bias). Science deliberately does the opposite: it tries to break its own theories through controlled experiments, peer review, and replication. A theory earns trust not by being proven true — you can never prove a universal claim absolutely — but by surviving repeated genuine attempts to prove it false. That's why 'it's just a theory' misunderstands what a scientific theory is: it's an explanation that has withstood serious efforts to destroy it.
The philosopher Karl Popper argued that what separates science from pseudoscience is falsifiability — a real scientific theory sticks its neck out by forbidding certain outcomes. Einstein's general relativity is his favorite example. It predicted that gravity would bend starlight by a precise amount, a bold claim that could easily have been proven wrong. In 1919 the astronomer Arthur Eddington measured star positions during a solar eclipse and found the light had bent almost exactly as Einstein predicted. Popper's point was that the theory's credibility came from its willingness to be tested and its survival of a test that could have killed it — not from being clever or elegant. A theory that forbids nothing, and so can never fail a test, explains nothing.