Input A yields outcome B.
We get that understanding this way:
https://youtu.be/EYPapE-3FRw
I love that whole series of lectures. They are his Cornell introduction to physics lectures and are a gold mine of basic scientific type thinking.
So far, science has not increased our knowledge of truth. That's damn tough to come by.
What it has done is very significantly expanded our understanding of the world. Our theories are far more predictive in far more contexts than ever!
But, that is it! Monkey see, monkey do.
Engineering is all about applying that understanding to solve problems in robust, efficient, safe ways.