Columbia subject headings:
Harvard subject headings:
Concrete (Philosophy)
Hegel, Georg Wilhelm Friedrich, 1770-1831
Hegel, Georg Wilhelm Friedrich, 1770-1831--Contributions in the concrete.
Methodology.
Self-evidence (Logic)
Whitehead, Alfred North, 1861-1947
Whitehead, Alfred North, 1861-1947--Contributions in the concrete.
Princeton subject headings:
Concrete (Philosophy)
Hegel, Georg Wilhelm Friedrich, 1770-1831.
Methodology.
Whitehead, Alfred North, 1861-1947.