Who created God?

How scholars have understood it

Three key terms, in everyday words.

• Contingent (mumkin): something that exists but could have not existed. You, this table, the Sun. Its existence is "borrowed": it needs something else to explain why it exists.
• Necessary (wājib al-wujūd, "necessary of existence"): something whose existence is not borrowed — it could not fail to exist. It needs no cause, not because it is an exception, but because "needing a cause" is what being contingent means.
• Begins (ḥudūth, "origination"): coming into existence after not existing. Whatever begins is contingent.

The kalām argument (al-Ghazali). Kalām is Islamic rational theology. Al-Ghazali's version, in The Incoherence of the Philosophers: "Every being which begins has a cause for its beginning; now the world is a being which begins" (Wikipedia's translation). He also argued that a beginningless universe and an actual infinity of past events are absurd. This is the origin of what is now called the "kalām cosmological argument", whose modern form is: "Everything that begins to exist has a cause"; "The universe began to exist"; so the universe has a cause (Wikipedia).

Ibn Sina's "proof of the truthful" (burhān al-ṣiddīqīn). In the fourth part of al-Ishārāt wa al-tanbīhāt, and in al-Najāt and al-Shifāʾ, Ibn Sina argues from contingency, not from a beginning. A contingent thing needs an external cause. Apply this to the whole collection (jumla) of contingent things — even if it were infinite: the collection too needs a cause outside itself, and since that cause cannot be contingent, it must be necessary (Wikipedia, "Seddiqin argument"). When critics object that a whole need not share its parts' properties, Ibn Sina treats this as a concession: "in a certain way, this is the very thing that is sought". He also argued that a thing's essence (what it is) does not explain its existence (that it is), so existence must be given to it by a cause (Wikipedia, "Cosmological argument").

Al-Ghazali against the philosophers — and Ibn Rushd against al-Ghazali. Al-Ghazali accepted a creator but held that the philosophers (above all Ibn Sina) could not demonstrate their metaphysics with the logic they used elsewhere; three of their theses he judged unbelief, the first being "The theory of a pre-eternal world" (Wikipedia). Ibn Rushd's Incoherence of the Incoherence "defends the doctrines of the philosophers and criticizes al-Ghazali's own arguments" (Wikipedia). They agreed that God exists; they disagreed on whether the world had a beginning and how God's causation works.

Mulla Sadra's version. Mulla Sadra, in al-Ḥikma al-mutaʿāliya (the Asfār), starts not from contingent things but from existence itself. He treats existence as one reality that differs among its instances "only in perfection and imperfection and in intensity and weakness", and calls the Necessary Existent "Pure Existence than which nothing is more complete" (Wikipedia, "Seddiqin argument"). The idea: existence, followed to its most complete degree, is God.

Divine simplicity, in plain words. Classical theism holds that God has no parts — not physical parts, and not even a distinction between what He is and that He is. Something made of parts depends on its parts and on whatever put them together, so it would be contingent. That is why, on this view, a necessary being must be simple. This is also the reply to Dawkins: the argument is not for a complex designer who would need explaining, but for a simple ground of existence.