First, a true principle and anything built on true principles are timeless. If pepperoni pizza is the Truth then quite frankly we should be eating it for the rest of our life.

Second, the founding fathers never said this. They created the Constitution as a living document. Also, almost every major problem in this country can be traced back to deviation from what the constitution set forth. "Congress shall issue money." J/k we're gonna have a private, un-auditable Federal Reserve print money out of thin air and loan it at interest.