Have no power, by taxation or otherwise, to retard, impede, burden or in any manner control the operations of the constitutional laws enacted by Congress.

When a law is in its nature a contract, when absolute rights have vested under that contract, a repeal of the law cannot divest those rights.

I have always believed that national character... depends more on the female part of society than is generally imagined. Precepts from the lips of a beloved mother... sink deep in the heart, and make an impression which is seldom entirely effaced.

A legislative act contrary to the Constitution is not law.

State inspection laws, health laws, and laws for regulating the internal commerce of a State, and those which respect turnpike roads, ferries, &c. are not within the power granted to Congress. ... Inspection laws, quarantine laws, health laws of every description, as well as laws for regulating the internal commerce of a State, and those which respect turnpike roads, ferries, &c., are component parts of this mass. No direct general power over these objects is granted to Congress, and, consequently, they remain subject to State legislation.

An unlimited power to tax involves, necessarily, a power to destroy; because there is a limit beyond which no institution and no property can bear taxation.

What is it that makes us trust our judges? Their independence in office and manner of appointment.