Cicero and the
Natural Law (c. 52 BC)
There in fact a true law - namely, right reason - which is in accordance with nature,
applies to all men, and is unchangeable and eternal. By its commands this law summons men
to the performance of their duties; by its prohibitions it restrains them from doing wrong. Its
commands and prohibitions always influence good men, but are without effect upon the bad. To
invalidate this law by human legislation is never morally right, nor is it permissible ever to
restrict its operation , and to annul it wholly is impossible. Neither the senate nor the people
can absolve us from our obligation to obey this law, and it requires no Sextus Aelius to expound
and interpret it. It will not lay down one rule at Rome and another at Athens, nor will it be
one rule to-day and another tomorrow. But there will be one law, eternal and
unchangeable, binding at all times upon all peoples; and there will be, as it were, one common
master and ruler of men, namely God, who is the author of this law, it interpreter, and its
sponsor. The man who will not obey it will abandon his better self, and, in denying the true
nature of a man, will thereby suffer the severest of penalties, though he has escaped all the other
consequences which men call punishments. (Cicero, THE REPUBLIC, II, 22.)
Out of all the material of the philosophers' discussions, surely there comes nothing more
valuable than the full realization that we are born for Justice, and that right is based, not
upon man's opinions, but upon Nature. This fact will immediately be plain if you once get a
clear conception of man's fellowship and union with his fellow-men.... Nay, if bad habits
and false beliefs did not twist the weaker minds and turn them in whatever direction they are
inclined, no one would be so like his own self as all men would be like all others. (Cicero, THE LAWS, I, 10, 28-29.)