Classification in documentation is a tool for selection. It is essentially a 'finding system' for subject items... It is an artificial language, designed as a tool to aid in the selection of information from a store in response to search questions. The classification serves to standardise subject description, so that the description of a subject used by indexer and inquirer are more likely to coincide, thus maximising the probability of finding all items relevant to an inquiry.

p. 12-13. - Classification and indexing in science (1958) - Chapter 1: The need for classification