Of course, all of these policies are supposed to have been backed up by scientifically proved economic theories – saying that markets are best left alone, that making the rich richer makes everyone richer, that welfare spending and protection of worker rights only make people lazy and dependent, and so on. Most people have accepted these theories without much questioning because they are based on "expert" advice.
However, all these economic theories are at least debatable and often highly questionable. Contrary to what professional economists will typically tell you, economics is not a science. All economic theories have underlying political and ethical assumptions, which make it impossible to prove them right or wrong in the way we can with theories in physics or chemistry. This is why there are a dozen or so schools in economics, with their respective strengths and weaknesses, with three varieties for free-market economics alone – classical, neoclassical, and the Austrian