God, Philosophy and Science

Craig opens his essay with Leibniz's famous question: "Why is there something rather than nothing?" Recalling this question's place in the history of philosophy — a question that has occupied thinkers from Aristotle to Wittgenstein — he presents Leibniz's own answer: the idea of a "Necessary Being" whose reason for existing lies within itself. Craig notes that some atheist philosophers, Bertrand Russell among them, have attributed this status not to God but to the universe itself: "the universe just is, and that's all." Craig finds this unsatisfying, and devotes the rest of the essay to answering that claim.

From here Craig formally constructs his central argument: the Kalam Cosmological Argument consists of three simple steps — everything that begins to exist has a cause, the universe began to exist, therefore the universe has a cause. Craig notes that this argument was in fact developed by medieval Muslim theologians (hence the name "kalam"), and that it entered Western philosophy precisely through that tradition. The main dispute lies in the second premise, and Craig defends it from two separate directions — philosophical and scientific.

On the philosophical side, Craig argues that a "real infinite" cannot exist in the physical world — using examples like the famous Hilbert's Hotel paradox, he shows that logical absurdities, such as a hotel with infinitely many rooms, all full, still being able to accommodate a new guest, demonstrate that infinity cannot actually exist in the real world. If past events were infinite, such contradictions would be unavoidable. Therefore the past must be finite, meaning the universe must have had a beginning.

On the scientific side, he points to Big Bang cosmology — redshift, the abundance of helium, the cosmic background radiation discovered in 1965. As his strongest evidence he cites the theorem proven in 2003 by three leading cosmologists, Borde, Guth, and Vilenkin: any expanding universe model, regardless of the physical details of its earliest moments, must have an absolute boundary in the past. For Craig, the power of this proof lies precisely in the fact that it holds true no matter which speculative model turns out to be correct. Vilenkin himself states the conclusion bluntly: "There is no escape; they have to face the problem of a cosmic beginning" (p. 165).

The second scientific argument comes from the second law of thermodynamics: as a closed system, the universe must eventually reach an equilibrium state called "heat death" — stars will burn out, black holes will evaporate, everything will settle into a cold, dark equilibrium. If the universe were eternal, it would have already reached this equilibrium an infinite time ago — but it hasn't, which means the universe had a beginning. Craig backs this conclusion with similar statements from physicist Paul Davies.

In defending the first premise, Craig analyzes and rejects at length Paul Davies's scenario of "causeless" emergence from the quantum vacuum — arguing that even the quantum phenomenon called particle-antiparticle pair "creation" is really the conversion of energy into material form, not creation from absolute nothingness. He recalls that even a skeptical philosopher like David Hume, in an 1754 letter, admitted he never claimed something could arise without a cause — only that this principle couldn't be proven.

The essay's most original part comes in its final section: Craig argues for why the cause of the universe must be a "personal Creator." The logic runs like this: if an eternal cause were simply the operation of mechanical, unchanging conditions, its effect would also be eternal — for example, if water freezes because the temperature is below zero, and the temperature has eternally been below zero, then the water would have been eternally frozen too. The only way a temporal effect can arise from an eternal cause is if that cause is a personal agent who freely chooses — like a man who has sat forever finally choosing to stand up.

In closing, Craig concludes that the cause of the universe must be an uncaused, immaterial, eternal, unchanging, timeless, and freely willing Agent, and argues from there — building on the Kalam Cosmological Argument — that belief in God's existence is rational.

• 6 independent essays, 256 pages total — each in the format of a separate philosophical paper, with extensive footnotes and citations.
• Craig's essay is written in classic analytic-philosophy style: the argument is first laid out in formal steps, then each premise is defended separately.
• Scientific citations (Vilenkin, Davies, Hawking) are quoted directly from source and precisely footnoted.
• The translation (Zikri Yavuz) stays faithful to the philosophical terminology, though this sometimes makes it heavy going.
• The author biographies at the front of the book are worth reading before each essay — they clarify the authors' academic backgrounds.