Columbia subject headings:
Harvard subject headings:
Belief and doubt--History--20th century.
Italy--Intellectual life--20th century.
Nihilism (Philosophy)--History.
Nihilism--Religious aspects--Christianity
Philosophy and religion--History--20th century.
Philosophy, German--Influence.
Philosophy, Italian--20th century.
Philosophy, Modern--20th century.
Rationalism--History--20th century.
Skepticism--History--20th century.
Princeton subject headings:
Belief and doubt--History--20th century.
Italy--Intellectual life--20th century.
Nihilism (Philosophy)--History.
Nihilism--Religious aspects--Christianity.
Philosophy and religion--History--20th century.
Philosophy, German--Influence.
Philosophy, Italian--20th century.
Philosophy, Modern--19th century.
Philosophy, Modern--20th century.
Rationalism--History--20th century.
Skepticism--History--20th century.