  One of the more important contributions of Crescas to the history of philosophy is his critique of Aristotelian  science.[19]  This critique takes  place in the second part of the first essay in Or Hashem. Crescas’s opinions regarding natural science are influenced by the new Christian physics of the 14th century, and especially by thinkers like Ockham, Buridan, and Oresme (Pines 1967). Another source of Crescas’s science appears to be the lost book of Abner, The New Philosophy. But in this case, as in others, Crescas weaves together different sources and utilizes them freely in his goal to build one unified opinion. This original thought influenced occidental philosophy, finding its way via translation into Pico della Mirandola’s book Examen Vanitas Doctrinae Gentium, and later into Spinoza.  Some of his most well known opinions include the existence of the void, the existence of infinitude of worlds, and the existence of time without movement.