United States in 1872, when it decided that Congress could make
government notes a legal tender for debts contracted before the
law was passed.[Footnote: The Legal Tender Cases, 12 Wallace's
Reports, 457, 529.] It had held precisely the contrary two years
before,[Footnote: Hepburn _v._ Griswold, 8 Wallace's
Reports, 603.] but it was by a bare majority and in the face of a
strong dissenting opinion. In the opinions filed in the second
case stress was laid upon this division of the court.[Footnote:
12 Wallace's Reports, 553, 569. See George F. Hoar,
"Autobiography," I, 286.]

The word "established" is often used to describe the kind of
precedent to which courts are bound to adhere. What serves to
establish one? Long popular usage, repeated judicial
affirmations, and general recognition by approved writers on
legal topics. Of these, in fact, the last is probably the most
powerful. Lawyers and courts, in countries without codes, get
their law mainly from the standard text-books. Such authors as
Coke, Blackstone, Kent and Cooley are freely cited and relied on
as authorities by the highest tribunals.[Footnote: See, for
instance, Western Union Telegraph Co. _v._ Call Publishing
Co., 181 United States Reports, 101; Louisville Ferry
Co. _v._ Kentucky, 188 United States Reports, 394, 397.] It
is by the writings of such men that judicial precedents are
sifted and legal doctrines finally clothed in appropriate terms
and arranged in scientific order.

The English courts long ago declared it to be a rule of law to
prevent perpetuities that no estate in lands could be created
which was not to commence within the compass of a life or lives