Science is biology, engineering, chemistry, physics. “Economics” is not science, although it desperately wants to be known as one. In reality, it is below psychology
As one gets into advanced economics, not the simplified introductory economics of introductory college courses, lurking just below the surface where most people never see it is math, hard math. Stuff that makes calculus, differential equations, and even Laplace transforms look like a Sunday School picnic.
I have never seen a liberal who really understood advanced math, most top out with arithmetic, and simple arithmetic at that. This never prevents them from having a strong opinion based on nothing but ignorance.
But, if one ever studies enough economics to get into the really advanced areas, he will soon see that it really is a branch of science.