In a philosophy of religion course at an American university , students waded through difficult arguments for and against the possibility of proving God ′ s existence . After weeks of studying Anselm ′ s ontological argument , Kant ′ s critique of theistic proofs , and St . Aquinas ′ s cosmological argument , the professor announced one day that a big exam would be postponed . An exultant student exclaimed , “ There indeed is a God ! ”