Pierre Duhem considered that these condemnations "destroyed certain essential foundations of Peripatetic physics". Although the Aristotelian system viewed propositions such as the existence of a vacuum to be ridiculously untenable, belief in Divine Omnipotence sanctioned them as possible, whilst waiting for science to confirm them as true. From at least 1280 onward, many masters at Paris and Oxford admitted that the laws of nature are certainly opposed to the production of empty space, but that the realisation of such a space is not, in itself, contrary to reason. These arguments gave rise to the branch of mechanical science known as dynamics.