The Scientific Method
Belief and Faith
Deciding the truth of a statement about the world is at the heart of science. We may beleive certain ideas for many reasons. We may not even question those ideas, if we arrive at them through direct experience, if they come from people we trust or respect. It would be extremely difficult to go through life without excepting some ideas on the basis of trust or experience. When we except an idea, for whatever reason, we are said to believe.
Since there are an infinite number of beliefs, from the ridiculous to the plausable we need a method to distinguish those beliefs which are consistant with reality. The scientific method is our best solution to this problem.
How Science Works
The scientific method has four steps.
Before we make any assumptions about the phenomenon we need to observe and describe the phenomena clearly.
Once we have identified a phenomena that needs explanation, the next step is to think about how the phenomena can happen either by a causal mechanism, or mathematical relation pehaps even an educated guess. In technical language, we form an hypothesis. In forming an hypothesis we may perform tests by gathering data and performing experiments.
If the result of our tests agrees with our hypothesis, the results add weight to our initial hypothesis it does not mean that our hypothesis is true. If the results of the experiments disagree with our hypothesis, the initial hypothesis is WRONG. The initial hypothesis must be modified or rejected. This one statement sums up the power of the scientific method. It doesn't matter how smart you are or how elegant the theory. If it disagrees with experiment, it is wrong. This one statement sums up the power of the scientific method over other systems of reasoning such as faith or belief.
Our theory attains more credibility when it is used it to predict the result of another related phenomena or explain observed results the test against reality agrees with prediction.
Reproducibility of Results
The final stage of the scientific method is to ensure that the predicted results are reproducible by several independent experimenters with properly performed experiments. The point about experiments is that the results should be repeatable which is why scientists go to great pains to explain what equipment was used, how the experiment was performed along with the results we obtained and a conclusion about the results obtained.
As more evidence is gathered in support of a theory in time it may become regarded as a theory, model or even a law. It may become established to the point that it becomes an accepted scientific fact. Even when an idea is taken as fact, new evidence may require that the range of application over which it agrees with reality to be changed. A good example of this is Newton's laws of motion. While Newton's laws work fine when applied to the world of our everyday experience, these laws break down at speeds close to the speed of light. Einstein's, theory of relativity refined the existing laws of motion to work at speeds close to the speed of light. The new theory also had to agree with Newton's laws at low speeds. Even with all the weight of evidence from experiments and predictions, a scientific theory is never proven. It can only ever be disproved.