The cosmological argument: Aquinas' first three Ways (motion, cause, contingency), the Kalam argument, and the challenges of Hume and Russell.

What this dot point is asking

This WJEC theme asks you to explain and evaluate the cosmological argument, the a posteriori argument that the existence of the universe requires God as its cause. You need Aquinas' first three Ways (motion, cause and effect, contingency and necessity), the Kalam version, and the major criticisms, above all those of David Hume and Bertrand Russell. AO1 wants accurate exposition of the argument; AO2 wants a reasoned judgement on whether it succeeds.

The answer

Aquinas' first three Ways

• The First Way (motion or change). Things in the world are in motion (change). Whatever is moved is moved by another. An infinite regress of movers is impossible, so there must be a first unmoved mover, which Aquinas calls God.
• The Second Way (cause and effect). We observe an order of efficient causes. Nothing can be the cause of itself. An infinite regress of causes is impossible, so there must be a first uncaused cause.
• The Third Way (contingency and necessity). Contingent things (which can come into and go out of existence) do not have to exist. If everything were contingent, at some time nothing would have existed, and nothing would exist now. So there must be a necessary being whose existence is not contingent, namely God.

The Kalam argument

The Kalam argument is distinctive in claiming the universe had a temporal beginning, a claim its defenders link to Big Bang cosmology, and in arguing that the cause must be a personal, uncaused agent who chose to bring time into being.

The challenges of Hume and Russell

• Hume. We cannot validly infer a cause of the whole universe from causes operating within it (the fallacy of composition). The concept of a necessary being may be incoherent, since for Hume nothing whose existence we can conceive is logically necessary. And once each part of the universe is explained, the whole needs no further explanation.
• Russell. In his 1948 debate with Copleston, Russell argued that the universe is "just there, and that's all", a brute fact. Demanding a cause of the universe as a whole is, he held, a mistake; the series of causes need have no first term.

Defenders reply that the argument concerns the explanation of existence rather than logical necessity, and that calling the universe a brute fact is not an explanation but a refusal to seek one.

Examples in context

Model paragraph (does "the universe just is" answer the question?). The clash between the cosmological argument and Russell's brute-fact reply turns on what counts as an explanation. The argument assumes the "principle of sufficient reason", that for everything that exists there is a reason why it exists rather than not. If that principle holds, then the universe, as a collection of contingent things, cannot be its own reason, and a necessary being is required to terminate the explanation. Russell simply declines the principle: the universe is "just there", and to ask why is to ask an illegitimate question. The dispute is therefore not over the logic of the argument, which is valid, but over a prior assumption. A strong evaluation recognises this, arguing either that rejecting the principle of sufficient reason is an arbitrary stopping point that science itself does not accept, or that Hume is right that we have no warrant to apply causal reasoning beyond the universe at all.

Try this

Q1. What does the First Way conclude God to be? [2 marks]

• Cue. An unmoved mover: the first cause of all change, which is itself unchanged.

Q2. State the three steps of the Kalam argument. [3 marks]

• Cue. Everything that begins to exist has a cause; the universe began to exist; therefore the universe has a cause.

Q3. Evaluate the view that the cosmological argument proves the existence of God. [20 marks]

• What the marker wants. A balanced argument weighing Aquinas and Kalam against Hume's fallacy of composition and Russell's brute fact, with a reasoned judgement on "proves".