The liberty mentioned in the Fourteenth Amendment of the Federal Constitution "means not only the right of the citizen to be free from the mere physical restraint of his person, as by incarceration, but the term is deemed to embrace the right of the citizen to be free in the enjoyment of all his faculties; to be free to use them in all lawful ways; to live and work where he will; to earn his livelihood by any lawful calling; to pursue any livelihood or avocation, and for that purpose to enter into all contracts which may be proper, necessary and essential to his carrying out to a successful conclusion the purposes above mentioned." This was written by MR. JUSTICE PECKHAM in Allgeyer v. Louisina1 where it was held that a state statute prohibiting in effect a contract of insurance with a company resident in a foreign state of the Union was unconstitutional.
Knowlton, Jerome C. "Freedom of Contract." Mich. L. Rev. 3 (1905): 619-34.