Ibn Sīnā and his followers added to this that a contingent being cannot be nonexistent except through a cause. The majority disputed this with him; even his fellow philosophers challenged him on it.

I later found that Ibn Rushd the Younger had also mentioned what I have stated here: that Ibn Sīnā took this method from the theologians. He mentioned it in his book entitled The Incoherence of the Incoherence. For Abū Hāmid al-Ghazālī included in his book, The Incoherence of the Philosophers, a discussion explaining the philosophers’ inability to prove the existence of a Maker of the world.

[Al-Ghazālī’s discussion of the philosophers’ inability to prove the existence of a Maker of the world]

He said:

“We say: People fall into two groups. One consists of the people of truth. They hold that the world is originated and know necessarily that an originated thing cannot come into existence by itself, but requires a Maker. Their position affirming a Maker is therefore intelligible.

“The other group consists of the eternalists. They hold that the world is eternal, just as it is, and do not affirm its Maker. Their belief is intelligible, even though the evidence demonstrates its falsity.