Technically, both the Ontological and Cosmological argument involve "begging the question"; both routes of thinking involve unjustified assumptions about the state of either the universe (cosmological) or the possibility of god (ontological) in its premise. Typically, conclusions made about a god have a circular contradiction if the flow of logic is separated into steps; coincidentally, the Teleological argument is the only argument posed that did not attempt to provide a stepwise route into the proving of a deity.
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