The Essentials Of American Constitutional Law – Francis Newton Thorpe – Platanus Publishing

"The powers of Congress are derived through this Constitution and are adequate to the legislative needs of the government thus created. Here again applies the principle as to proper legislative powers: "Let the end be legitimate, let it be within the scope of the Constitution, and all means which are appropriate, which are plainly adapted to that end, which are not prohibited, but consist with the letter and spirit of the Constitution, are constitutional." If this principle be true (and it lies at the basis of government in America), it seems unnecessary that the Constitution should specify, or enumerate the powers of Congress. These which are enumerated may not be said to be in any logical order. Doubtless the qualities of sovereignty are equal qualities—each essential to the supreme end and purpose of sovereignty—which end and purpose is to be and to remain sovereignty."