Any scientific theory has two well defined goals: to tie multiple part of the known together, and also tie those parts to some part of the unknown. Prediction

Any scientific theory has two well defined goals: to tie multiple part of the known together, and also tie those parts to some part of the unknown. Prediction is an important point, but it's just as important as meaningfully stitching together what's already known to produce new knowledge. I'm academically ignorant about economics, I'm honestly asking is there really a body of knowledge about economics, like different theories conversing between each other? Are theories built on top of each other?