In René Descartes, Meditations on First Philosophy, he talks about the distinction between God and existence. This article will argue that in René Descartes, Meditations on First Philosophy, Thomas Hobbes, Leviathan, both contrast how we know that God actually exists and how we know that what we perceive in this world also actually exists. This essay will begin by talking about René Descartes and his ideas about the existence of God and life itself with everything that lives in it. René Descartes proposes a thesis that everything we perceive in life is true when he says; “And so now it seems to me that I can postulate as a general rule that everything I perceive very clearly and distinctly is true” (Descartes, 24). A human being always constantly thinks about the things in life. René Descartes studied the things humans can perceive and imagine. He had the idea of ​​how do we know that something we imagined actually happened and we didn't dream it. René Descartes wrote this book to discover how we constantly imagine and perceive things throughout our lives; how we perceive it to be true and how we know it is true. He also asks how we can know that God really exists. Rene Descartes' book, Meditations on First Philosophy, was an interesting read. Many people have thought: how do we know that God really exists without any evidence of the fact? Descartes questions the existence of God when he says; “And certainly, because I have no reason to think that a deceiving God exists (and obviously I still do not know sufficiently whether a God exists)” (Descartes, 25). I hear people ask this question a lot. I have never heard it said, how do we know that we are not just imagining everything in life... middle of paper... in God you can't understand it because there is not enough evidence to fully understand God. This This essay has shown us like René Descartes and Thomas Hobbes they thought differently about both the existence of life and God. Rene believed that there were no limits to God. Thomas, on the other hand, believed that one could believe but not understand God. Rene showed us how we think constantly to things even when we imagine things that are not real and how do we know if something exists. Thomas, however, disagrees with him thinking that we should not trick our mind into imagining things that are not real because it would be a waste of our thinking. Works Cited Descartes, René. Meditations on first philosophy. Trans. Donald A. Cress. Indianapolis: Hackett Pub., 1993. Print.Hobbes, Thomas. Leviathan. Ed. AP Martinich and Brian Battiste. Peterborough, Ontario: Broadview, 2011. Print.