Classification
200 - Religion
300 - Social sciences
320 - Political science
330 - Economics
21
100 - Philosophy & psychology
7
900 - History & geography
7
301 - Sociology & anthropology
6
333 - Economics of land & energy
5
000 - Computer science, information & general works
4
140 - Specific philosophical schools
3
170 - Ethics
3
370 - Education
3
363 - Other social problems & services
2
380 - Commerce, communications & transportation
2
400 - Language
2
600 - Technology
2
630 - Agriculture & related technologies
2
120 - Epistemology, causation & humankind
1
304 - Factors affecting social behavior
1
340 - Law
1
410 - Linguistics
1
530 - Physics
1
610 - Medicine & health
1
700 - The arts; fine & decorative arts
1
800 - Literature & rhetoric
1