Do you believe in a deity? Either way, what is your reasoning? 'Theism' as it is used in Philosophy of Religion is the view that there is one supreme, perfect being who exists separately from the world, who is the creator and sustainor of the universe, who is conscious to the degree of being all-knowing; who is all-powerful, all and ever present, eternal, unchanging, existing necessarily, dependent of nothing else. In addition, Theism maintains that this being, who is called "God", loves and is concerned about humanity. It is claimed that Theism, as here understood, stands at the core of the three Abrahamic religions: Judaism, Christianity, and Islam.
So, the question that arises is "Are there any good reasons for thinking that such a being is real?" Depending on what you mean by "good reason", most Theists answer that question with a "Yes there are". The question then morphs into "Just what are these reasons and do they consititute "good" reasons?"
I maintain that there are no good reasons for thnking Theism is true and some plausible reasons for thinking it is false. If I am right, then most forms of Judaism, Chistianity, and Islam are wrong.