>Economics is clear when explaining its foundation: Markets are only as efficient as its participants are rational and fully informed.
Plus even more assumptions: that participants cannot game the system (by influencing laws, abusing power or monopoly, bribing others participants, controlling public opinion by friendly or owned mass media, forming cartels, etc).
Oh, and "rational" doesn't just mean "clearly thinking and clever", but also perfect calculating actors in a game-theoretic way.
Oh, and there are no factors outside of direct market control, from natural disasters and resources, to foreign country policies and such.
So all those hold even remotely true only in some magic unicorn land.
Plus even more assumptions: that participants cannot game the system (by influencing laws, abusing power or monopoly, bribing others participants, controlling public opinion by friendly or owned mass media, forming cartels, etc).
Oh, and "rational" doesn't just mean "clearly thinking and clever", but also perfect calculating actors in a game-theoretic way.
Oh, and there are no factors outside of direct market control, from natural disasters and resources, to foreign country policies and such.
So all those hold even remotely true only in some magic unicorn land.