If men were angels, no government would be necessary. If angels were to govem men,

If men were angels, no government would be necessary. If angels were to govem men, neither external nor internal controls on government would be necessary. In framing a government which is to be administered by men over men, the great difficulty lies
in this: you must first enable the goverment to control the governed, and in the next place oblige it to control itself.
-James Madison, Federalist Paper 51
Which concept is James Madison discussing?
A strict interpretation
B. individual rights
C. checks and balances
D. federalism