At university Swammerdam engaged deeply in the religious and philosophical ideas of his time. He categorically opposed the ideas behind spontaneous generation, which held that God had created some creatures, but not insects. Swammerdam argued that this would blasphemously imply that parts of the universe were excluded from God's will. In his scientific study Swammerdam tried to prove that God's creation happened time after time, and that it was uniform and stable. Swammerdam was much influenced by René Descartes, whose natural philosophy had been widely adopted by Dutch intellectuals. In "Discours de la methode" Descartes had argued that nature was orderly and obeyed fixed laws, thus nature could be explained rationally.