 Material consequences are those which do satisfy the necessary truth-preservation criterion (TP) but do not satisfy the substitutional criterion (ST) (Crimi 2018). At first sight, Buridan’s distinction between formal and material consequence seems very similar to, for example, Abelard’s distinction between perfect and imperfect inferences. There is, however, a fundamental difference; nowhere does Buridan suggest that formal consequences are valid in virtue of their form, as Abelard had claimed for the ‘complexio’ of perfect inferences (Dutilh Novaes and Bosman 2017). He does say that the validity of a material consequence is made evident only by means of a reduction to a formal consequence (TC, 1.4), but this observation pertains to the epistemic level of how the validity of a consequence is made apparent to us, not to the quasi-metaphysical level of what grounds  it.[11]