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How did Avicenna’s temporally modalized syllogisms use phrases such as at all times?

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Avicenna The title page of the 1556 edition of Avicenna's *The Canon of Medicine* (*Al-Qanun fi al-Tibb*). This edition (sometimes called the 1556 Basel edition) was translated by medieval scholar Gerard of Cremona.

Avicenna, a prominent Persian philosopher and scientist, developed an original theory of "temporally modalized" syllogisms that moved beyond traditional Aristotelian logic.12

In this system, he incorporated specific temporal modifiers into the premises of categorical propositions to account for the duration or frequency of a predicate's application to a subject. Phrases such as "at all times," "at most times," and "at some time" were used to qualify these premises, allowing for a more nuanced logical analysis of how properties relate to subjects over time. By utilizing these modifiers, Avicenna was able to refine the quantification of predicates, distinguishing his work from the earlier, more rigid interpretations of the school of Baghdad.12