 It is significant that Simon refers to Averroes’ commentary on the Physics, thus illustrating the importation of the Aristotelian (meta)physical framework into logical analyses. We here have the notion of ‘valid in virtue of form’ (as with Abelard’s ‘complexio’), and the association of form and formality with the idea of substitution of terms (ST). Other authors of the same period, John Duns Scotus for example, also use the phrase ‘consequentia formalis’ and its variants, but not in the substitutional sense of holding ‘in all matter’ (Martin 2005).