Philosophical process includes three fundamental questions: What is real? — Metaphysics.
What is true? — Epistemology. What is good? — Ethics.
Following Aristotle, scientists were involving science to explain Theory. Theory allows us to do things happen in the same way. By prognosis based on empirical method, not by intuitive guess, we can project observed events into the future or create a model, which simplify reality. Due to Theory we can make predictions with a high level of probability.