Universal Decimal Classification Apr 2026

To make this work, they needed a classification system that was:

The UDC divides all human knowledge into ten main "houses" (classes), numbered 0 to 9:

In the late 19th century, two Belgian visionaries, and Henri La Fontaine , looked at the world’s exploding volume of information and saw a looming "Pit of Despair"—a future where human knowledge would be lost simply because it couldn't be found. universal decimal classification

Their quest to catalog every piece of human thought led to the creation of the , a system built on the bones of the Dewey Decimal Classification but designed for far more than just books. The Vision: The Mundaneum

Using symbols like colons (:) or pluses (+) to show how different subjects—like Physics and Medicine —linked together to form new ideas like Biophysics . The System: A Mathematical Map of Mind To make this work, they needed a classification

Otlet and La Fontaine didn't just want a library; they wanted a "city of knowledge". In 1895, they founded the Mundaneum in Mons, Belgium—a pre-digital precursor to Google.

Able to cover every field of knowledge, from Philosophy to Engineering. The System: A Mathematical Map of Mind Otlet

Using numbers that any person, regardless of language, could understand.