The most fascinating aspect of the language and style of Tacitus is that they may be seen in evolution. If we set aside the Dialogus as a special case because of its subject matter, for which a Ciceronian style was virtually obligatory, we may follow Tacitus' style through a continuous process of development from the two monographs to the Histories and then to its culmination in his most mature work, the Annals—though to use this word ‘culmination’ may be to prejudge the issue. Of course stylistic change and development may be found in the works of many writers, Cicero and Propertius for instance, but in few writers if any is the development so clear to see, yet also so complicated, as in Tacitus.
E. Wölfflin, who began the systematic investigation of Tacitus' language and style, maintained that there is in Tacitus' writings a persistent and continuous movement away from normal, hackneyed and colourless expressions towards novelty, colour and dignity, towards what the Greeks called σενότης—or, as some have chosen to put the matter, Tacitus in diverging more and more from the ‘normal’ became progressively more ‘Tacitean’.