Columbia subject headings:
Certainty.
Mathematics--Philosophy.
Russell, Bertrand, 1872-1970.
Russell, Bertrand, 1872-1970. Principles of mathematics.
Harvard subject headings:
Certainty.
Mathematics--Philosophy
Russell, Bertrand, 1872-1970
Russell, Bertrand, 1872-1970. Principles of mathematics.
Princeton subject headings:
Certainty.
Mathematics--Philosophy.
Russell, Bertrand, 1872-1970.
Russell, Bertrand, 1872-1970. Principles of mathematics.