Economics is divided into two distinct analytical branches:
| Basis | Microeconomics | Macroeconomics |
|---|---|---|
| Unit of Study | Studies individual economic units (a single consumer, firm, or industry). | Studies the economy as a whole (aggregate national output, general price level, total employment). |
| Economic Instruments | Price mechanism (individual market demand and supply curves). | Aggregate Demand ($AD$), Aggregate Supply ($AS$), Fiscal & Monetary policy. |
| Central Problem | Optimal allocation of scarce resources among competing uses. | Determination of national level of income, output, and employment. |
| Assumptions | Assumes macro variables are constant (assumes full employment). | Assumes micro resource allocation is given. |
The Fallacy of Composition (Paradox of Thrift):
The logical fallacy of assuming that what is true and beneficial for a single individual is automatically true and beneficial for the entire economy as a whole:
- Individual Micro Level: If an individual worker saves more money from their paycheck, they build personal wealth and financial security.
- National Macro Level: If every single citizen simultaneously attempts to save more by cutting consumption, aggregate consumer spending ($C$) collapses. Firms experience unsold inventory, cut production, and lay off workers. National income plunges, leaving total societal savings lower or unchanged! This is Keynes' famous Paradox of Thrift.