The Nature of Science
The word “science” means “to know.” It should be restricted to what we can actually know about our world. If an idea is not testable, repeatable, observable, and falsifiable, it should not be considered scientific.
1. Testability in Science
Testability refers to the ability to run an experiment to test a hypothesis or theory. When designing a research hypothesis, the questions being asked by the researcher must be testable or the study becomes impossible to provide an answer to the inquiry.
2. Falsifiability in Science
A scientific hypothesis must be testable, but there is a much stronger requirement that a testable hypothesis must meet before it can really be considered scientific. This criterion comes primarily from the work of the philosopher of science Karl Popper, and is called "falsifiability".
Falsifiability is the capacity for some proposition, statement, theory or hypothesis to be proven wrong. That capacity is an essential component of the scientific method and hypothesis testing. In a scientific context, falsifiability is sometimes considered synonymous with testability.
3. Verifiability in Science
Verifiability means to confirm or substantiate that something is true. The opposite of to falsify is to verify. In scientific research, both are needed. If we only look for evidence to confirm what we believe is true, it could lead us to flawed conclusions.
4. Predictability in Science
One of the problems with credible falsifiable testing is that both the creationists and the evolutionists know most of the evidence that is out there. They can make predictions based on evidence they already know exists. The key is to find evidence predicted by one and not the other.