Columbia subject headings:
Ethics, Evolutionary.
Ethics.
Kant, Immanuel, 1724-1804--Ethics.
Harvard subject headings:
Ethics, Evolutionary.
Ethics.
Kant, Immanuel, 1724-1804
Kant, Immanuel, 1724-1804--Ethics.
Spencer, Herbert, 1820-1903.
Princeton subject headings:
Ethics, Evolutionary.
Ethics.
Kant, Immanuel, 1724-1804--Ethics.