Final answer:
James Madison, one of the Founding Fathers, observed the quoted phrase in his Federalist Paper No. 51, emphasizing the necessity of a government in society.
Step-by-step explanation:
The quoted phrase, "If men were angels, no government would be necessary", which emphasizes the necessity of government, was observed by James Madison. He was one of the Founding Fathers of the United States and a key contributor to the drafting and promoting of the United States Constitution and Bill of Rights. This quote comes from his Federalist Paper No. 51, in which he discussed the importance of checks and balances and the separation of powers in a government.
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