I should have been clearer with my pronouns. "They" was not referring to Senators as wiser, but to the drafters of the US Constitution.
Until 1913 US Senators were chosen by the State legislatures, not popularly elected.
"I shall not scruple to add, that such an institution may be sometimes necessary as a defense to the people against their own temporary errors and delusions."
Tyranny of the majority was of great concern to those drafting the US Constitution. One of the premises of the six year term for Senators was to allow them to enact legislation that went against the will of the majority because they were actually wise enough to know that the majority is not always right.
I should have been clearer with my pronouns. "They" was not referring to Senators as wiser, but to the drafters of the US Constitution. Until 1913 US Senators were chosen by the State legislatures, not popularly elected.
Federalist Paper #63 http://thomas.loc.gov/home/histdox/fed_63.html addresses your issue with laws that do not reflect the current opinion of the majority:
Tyranny of the majority was of great concern to those drafting the US Constitution. One of the premises of the six year term for Senators was to allow them to enact legislation that went against the will of the majority because they were actually wise enough to know that the majority is not always right.