Step 1: Internal vs external debt.
Internal government debt is owed to citizens of the same country, while external debt is owed to foreigners. The debate centers on whether internal debt burdens future generations.
Step 2: A. P. Lerner’s contribution.
A. P. Lerner, in his functional finance approach, argued that internal debt does not create a direct burden on future generations because repayment involves transfers within the same economy (from taxpayers to bondholders). Hence, society as a whole does not lose wealth.
Step 3: Eliminate other options.
- N. Gregory Mankiw, Martin Feldstein, and Harvey Rosen are modern economists but not the originators of this proposition.
Thus, the correct answer is (D) A. P. Lerner.