Definition of "categorical"

We now see that they [propositions] are either conditional or unconditional, or, as the logicians say, hypothetical (conditional) or categorical (unconditional).

1856, Robert Gordon Latham, Logic in the Application to Language‎

Daytime interests are clearly not such far-reaching psychical sources of dreams as might have been expected from the categorical assertions that everyone continues to carry on his daily business in his dreams.

1900, Sigmund Freud, translated by James Strachey, The Interpretation of Dreams: Avon Books, page 74