Formal and Material Consequences in Ockham and Buridan

William of Ockham and John Buridan provide different accounts of the distinction between formal and material consequences. Some consequences – in particular, enthymemes – that Ockham would classify as formal would be classified as material by Buridan. This paper explains this taxonomical discrepancy. It identifies the root of the discrepancy not in a difference between Ockham’s and Buridan’s notions of propositional hylomorphism but rather in Ockham’s endorsement of relational characterizations of consequences.