This short video by the Khan Academy presents a classic introduction to economic teaching. Starting with the quote by Adam Smith in "The Wealth of Nations" on the invisible hand, it shows how economics deals with the question of the allocation of scarce resources and shortly presents different questions addressed by microeconomics and macroeconomics. It further makes reference to questions of simplification in mathematical models.

This Perspective argues that ergodicity — a foundational concept in equilibrium statistical physics — is wrongly assumed in much of the quantitative economics literature. By evaluating the extent to which dynamical problems can be replaced by probabilistic ones, many economics puzzles become resolvable in a natural and empirically testable fashion.