In countries where the doctrine of the sovereignty of the
people ostensibly prevails, the censorship of the press is
not only dangerous, but absurd. When the right of every
citizen to a share in the government of society is
acknowledged, everyone must be presumed to be able to
choose between the various opinions of his
contemporaries and to appreciate the different facts from
which inferences may be drawn.
-Alexis de Tocqueville, Democracy in America
What is the central theme of this excerpt?