Economics (n.) An attempt to explain the world in large or small in terms of the physics of money.
Economics has been given a bad name by people who use it to explain why they are currently sticking a gun into one's ribs and extracting all one's money from one's pockets. The "free market", despite the wishful thinking of the kleptocratic political right wing, does not mean "a free market in violence, exploitation, corruption, and theft" but rather, a market in which there is perfect competition thanks to a neutral system of regulation that precisely stops the powerful from bullying the small and weak. True free markets are very rare, and economics as a science therefore remains largely theoretical.
The physics of money, or in a more general sense, of advantage, power, status, and wealth, are rather a good way of understanding the behaviour of individuals. The rule, "follow the money" is not so much a cynical over-simplification as a logical application of Occam's Razor.