Categories, and the categorical

Category, along with its inflections, may seem a puzzling word to students: its meanings in common parlance do not obviously correspond with its technical use by philosophers.

Public figures are reported in newspapers to have categorically denied something, and this is not a modern catchphrase: it dates from the 17th century. But what does it mean, and how does it connect with categories? How does one answer the questions of a student—who may know of Linnaeus with the categories that make up his taxonomy; or of the Categories of Aristotle; or of Kant with his Categorical Imperative?

When the Oxford philosopher Professor Gilbert Ryle gave his lectures, the place was so packed that people often had to sit on the floor. He had an unusual ability to clear the fog surrounding a word or concept.*  A flavour can be found in his entries in The Concise Encyclopaedia of Western Philosophy and Philosophers (Routledge 1989).  With the aid of his entry on categories, and of the English, Latin and Greek dictionaries, it is possible to give a passable summary of how this word has been used.

  1. It is originally the Greek legal word κατηγορία, meaning an accusation in court.
  2. Aristotle later borrowed the word to use as his technical term for a predication—and it is noteworthy that St Augustine later uses the Latin praedicamentum as its equivalent.  Aristotle distinguished several types of predication, or Categories, such as  kind, quality, quantity, relation, location, time, action, affection. The full discussion of these, and more, is in the Organon, his handbook of logic.
  3. Immanuel Kant (1784– 1804) coined the expression categorical imperative—again as a technical term in logic—which the OED defines as:
    ‘categorical imperative  n. in the ethics of Kant, the absolute unconditional command of the moral law, a law given by the pure reason, and binding universally on every rational will.’
  4. But as for common parlance, the word category has passed into general use in English to mean a group of things or beings about which an identical predication, or set of predications, can confidently be made, without doubt or hesitation. Hence the use of categorical, since before 1660, to apply to any assertion (or denial) that admits of no questioning.
    The OED acknowledges such usage, quoting:

¶  Bishop Martin Fotherby of Salisbury (1550-1620),
who refers to the atheist’s
‘simple and categoricall denying’

¶  Oliver Cromwell in a speech on 3rd April 1657:
“You do necessitate my answer to be categorical.”


* Ryle’s most well known book, The Concept of Mind, is still in print.