Why is there something rather than nothing?

A thing is contingent when it depends on something else to exist and might never have existed at all. A person exists because his parents met. He stays alive only because of air, food, water and the warmth of the sun. The sun exists because of hydrogen and gravity. It will burn only while its fuel lasts. Nothing in the world carries the reason for its own existence inside itself. Each thing has its existence on loan. The Qur'an puts three questions to those who deny their Maker. Were they made from nothing? Did they make themselves? Did they make the heavens and the earth?

Picture a line of railway carriages, each pulled by the one in front. Add ten, a thousand, or an endless line. Nothing moves unless there is an engine that pulls without being pulled. Or picture a man who asks a friend for a loan. The friend must first borrow it from a third man, who must borrow it from a fourth. If no one in the line actually has the money, the man is never paid. An endless number of borrowers is still not a lender. So the question "why is there this chain rather than none?" stands, however far back the chain goes.

There must be a being that depends on nothing and exists by its own nature. Muslim philosophers called it wajib al-wujud (the being whose existence is necessary). They called everything else mumkin al-wujud (the being whose existence is only possible). The necessary being must need nothing, or it would be one more borrower. It must have no parts, because a thing made of parts depends on its parts. And it can only be one. Two such beings would have to differ in something. Whatever made them differ would be a part or a limit. When the Qur'an speaks of the Face of Allah (﷾), it names an attribute, not a part, for there is nothing like Him.

Some reply that the universe itself is the thing that needs no cause. It fails every test. It has parts, from galaxies down to atoms, and a thing made of parts depends on them. Some say only its most basic stuff is necessary. That does not help. That stuff comes in a certain amount, obeys certain laws and comes in certain kinds. Each of these could have been different. The universe also changes every moment, and a thing that changes is always receiving something it did not have before. And nothing in it shows that it must exist, or must be the way it is. What exists by necessity cannot fail to exist and cannot be other than it is.

The question at its heart is the Qur'an's own: were they made from nothing, or did they make themselves? The argument's classical form was given by Ibn Sina, the Muslim philosopher known in Europe as Avicenna, who died in 1037. He set it out most famously in al-Isharat wa al-Tanbihat (Pointers and Reminders). Thomas Aquinas, a Christian thinker of the thirteenth century, read Avicenna in Latin. He built his Third Way, the third of his five proofs of God (﷾), on the same distinction. In 1714 Leibniz, a German philosopher, argued that the reason for the whole chain of dependent things must lie outside it, in a necessary being. Western textbooks often call it Leibniz's argument. Ibn Sina had set it out nearly seven hundred years before him.

Paul, a Christian missionary of the first century, told the philosophers of Athens that God (﷾) is not served by human hands. It is not as though He needed anything. He added that God (﷾) gives life and breath to all. The Bible and the Qur'an agree that the Creator needs nothing.

Paul's words "as though he needed any thing" raise a problem for Christians. The New Testament Gospels show Jesus hungry and asleep. Christians answer that only his human nature hungered. But the creeds say the one who hungered and slept is one person, God the Son. So the person they call God needed food and sleep. Whoever needs anything is a borrower, not the One who needs nothing.

The Qur'an puts the whole argument into one verse: people stand in need of Allah (﷾), and Allah (﷾) is free of all needs. It calls Him al-Samad (the one all others depend on), and the First and the Last. Two short verses draw the line between the borrowed and the necessary. All that is on earth will perish, and only the Face of the Lord remains. The Prophet (ﷺ) taught Muslims a prayer for each night before sleep. In it they say that Allah (﷾) is the First, with nothing before Him, and the Last, with nothing after Him.

Some atheists and agnostics say the existence of the universe needs no explanation. In his 1948 debate with Copleston, Bertrand Russell said it is simply there, and that is all.

Buddhism does not ask why there is anything at all. Things arise from conditions, the round of rebirth has no known beginning, and the Buddha set aside whether the cosmos is eternal.

The argument from contingency took its classical form with Ibn Sina. It passed into Western thought through Aquinas and Leibniz.