Columbia subject headings:
Contradiction.
Dialectic.
Hegel, Georg Wilhelm Friedrich, 1770-1831.
Heraclitus, of Ephesus.
Marx, Karl, 1818-1883.
Piaget, Jean, 1896-1980.
Harvard subject headings:
Contradiction.
Dialectic.
Hegel, Georg Wilhelm Friedrich, 1770-1831
Heraclitus, of Ephesus.
Marx, Karl, 1818-1883
Piaget, Jean, 1896-1980.
Princeton subject headings: