The choice and nature of the relations amongst the quotations / ‘tesserae’ of the classical sources chosen as well as the connotation of the story’s only character (the Pisan exile) make clear what Alberti’s literary operation in Hostis is all about.
The author has collected and elaborated all classical passages he knew of which discussed, from various points of view, how to treat one’s enemy. As Alberti himself was an exile, of illegitimate birth in a family of exiles, it is clear that this theme touched him greatly and was to him of extreme moral importance.
His thoughts therefore are a lay and disenchanted reflection on the decay of human society where everyone’s life is influenced not by divine will nor by the ‘political’ decisions of many, but by the choices and behavior of single individuals who often are trapped in the chains of a mechanical sequence of offences and revenge.
Therefore, the fact that in Hostis the ruin of Pisa is ascribed to the plots of a single individual, although being a variant as regards to the Medieval chronicle source, is crucial in order to understand correctly Alberti’s thought.
This interpretation is confirmed also by the context in which the work is located, viz. in the sequence of texts that make up the III Book of the Dinner pieces. In fact, as Roberto Cardini notes, “the single Dinner pieces are not so much autonomous works but parts of one only text or speech, persuasive like an argumentation and just as rigorous as a syllogism” and the III Book, in particular, is all about ambition, strife, affront, revenge and calamity.