Commentary Par XXIX 7-8

Some (incorrectly) believe that what is described as being of immeasurably short duration is Beatrice's smile (see Payton [Payt.1995.1], p. 439): 'The longer it is thought about, the smaller the exact instant is....  How long did Beatrice smile?  How brief a moment can you conceive?' Payton has not digested Cornish's explanation ({Corn.1990.1, pp. 6-7}), not of Beatrice's smile, but of her silence, which is the issue here: 'For Aristotle an instant (or the "now," as he called it) is the temporal equivalent of a point on a line; yet time is no more made up of these "nows" than a line is composed of geometrical points' (p. 7).  She points out that Porena before her had correctly characterized the temporal nature of Beatrice's silence (DDP Porena.Par.XXIX.4-6) as indeed having measurable duration.  Porena suggests that the amount of time for half the rising or setting Sun or Moon to rise completely above or to sink completely below the horizon is a little more than a minute, certainly a measurable time.  Cornish might have observed that Bosco/Reggio (DDP Bosco.Par.XXIX.1-9) had supported Porena's thesis.