The Scientific Method
The way that we do science is that we follow a set of guidelines called "The Scientific Method". This method helps us make sure that we test our ideas in such a way that we've done our best to remove our own opinions and personal biases from the process. Removing personal opinions and biases, and focusing on what the evidence is telling us is absolutely vital to science. It is the heart of everything that we, as scientists, try to do every day.