Not so, I can watch an airplane fly and I can drop a rock and see the results of gravity but I cannot make a rock come to life.
But the explanations for why the airplane flies or why the rock falls are scientific theories, just like the explanation on how we came to be. But if you rely on your eyes for everything then do you doubt the existence of an atom or the concept of something traveling faster than the speed of ight? Do you dismiss physics or asronomy since much of that is based on theory as well?