Roget's plan of classification
ClassSection
1.Abstract relations1.existence
2.relation
3.quantity
4.order
5.number
6.time
7.change
8.causation
2.Space1.generally
2.dimensions
3.form
4.motion
3.Matter1.generally
2.inorganic
3.organic
4.Intellect1.formation of ideas
2.communication of ideas
5.Volition1.individual
2.intersocial
6.Affections1.generally
2.personal
3.sympathetic
4.moral
5.religious

Roget, Peter M. 1852, Thesaurus of English words and phrases, classified and arranged so as to facilitate the expression of ideas and assist in literary composition. London etc.: Longmans, Green & Co.

http://en.wiktionary.org/wiki/Wiktionary:Roget_Thesaurus_Classification