Objection 1: The argument from fine-tuning is just another god-of-the-gaps argument. It amounts to saying, “We don’t know how the universe came to be fine-tuned to permit life, therefore God did it.”
This is a common mischaracterization. The argument does not use God to fill a gap in our knowledge. Instead, it weighs the explanatory power of the available competing hypotheses (i.e., chance, necessity and design) and rules in favor of the one which is most plausibly affirmed. This is known as an inference to the best explanation, and it is formed on the basis of what we know, rather than what we do not know. Given what we know (i.e., our universe is life-permitting only because certain physical constants and quantities fall into an extraordinarily narrow range of possible values), the design hypothesis is a better explanation than either chance or necessity. Abductive arguments like this are a common form of everyday and scientific reasoning.
Objection 2: The argument is fallacious because it presents us with a false dichotomy.
There is no false dichotomy present in the fine-tuning argument. The alternatives considered by the argument exhaust the range of possibilities. The Stanford Encyclopedia of Philosophy notes that there are only two historically discussed alternatives to design which could account for the fine-tuning of the universe: necessity and chance.2
Objection 3: If the universe weren’t fine-tuned, we wouldn’t be here to observe it. Therefore, we shouldn’t be surprised by fine-tuning, and we shouldn’t waste time trying to explain it.
It is true that, given the fact that we’re here and we’re alive, we should expect to observe a life-permitting universe. This is called the Anthropic Principle. But that expectation, and our observations which confirm it, do nothing to explain why the universe is life-permitting when it didn’t have to be. A life-prohibiting universe is vastly more probable than a life-permitting one, so why does a life-permitting universe exist? What is the best explanation? Is it chance, necessity, or design? Fine-tuning cries out for an explanation, but the anthropic principle is not the answer. The Stanford Encyclopedia of Philosophy is helpful once more: “While trivially true, [the anthropic] principle has no explanatory power, and does not constitute a substantive alternative explanation.”3
Objection 4: If God created and fine-tuned the universe, who created God?
The universe had a beginning4, so it makes sense to ask who or what created it. God, on the other hand, is eternal5, so it’s a category mistake to ask who created Him. It would be like asking if pencils were happy. Pencils are not in the category of things that have emotions, so it’s a meaningless question. In the same way, God is not in the category of things that have a beginning, so it’s meaningless to ask who created Him.
But even if the objection were valid, we still wouldn’t need to offer an explanation of our explanation. Philosopher William Lane Craig writes, “In order to recognize an explanation as the best, one needn’t have an explanation of the explanation. This is an elementary point concerning inference to the best explanation as practiced in the philosophy of science. If archaeologists digging in the earth were to discover things looking like arrowheads and hatchet heads and pottery shards, they would be justified in inferring that these artifacts are not the chance result of sedimentation and metamorphosis, but products of some unknown group of people, even though they had no explanation of who these people were or where they came from.”6
Craig goes on to argue that if we make explanations of our explanations a requirement, then every explanation would lead to an infinite regress of further explanations, so that nothing could ever be satisfactorily explained. We simply don’t need to have an explanation of God in order to infer His activity as the best explanation of fine-tuning.
(We address this objection in more depth here.)
Objection 5: There are so many randomly ordered universes – perhaps an infinite number – that some of them are bound to be fine-tuned for life. Ours just happens to be one them.
This objection points to the multiverse as the answer to the problem of fine-tuning, but the multiverse faces a serious problem of its own, namely that there is no evidence for it. Physicist John Polkinghorne writes, “Let us recognize these speculations for what they are. They are not physics, but in the strictest sense, metaphysics. There is no purely scientific reason to believe in an ensemble of universes.”7 Leading cosmologist George Ellis agrees: “Nothing is wrong with…philosophical speculation, which is what multiverse proposals are. But we should name it for what it is.”8 The only reason to postulate a multiverse is to diminish the strength of the design inference by increasing the probability of fine-tuning. But it’s obviously fallacious to think one has explained fine-tuning by merely imagining a solution.
Furthermore, we have good reasons to think that the multiverse – if it exists – would have to have a beginning, and that beginning would require both a sufficient cause and fine-tuned initial conditions.9 So while the multiverse hypothesis pushes the problem back a notch, it does nothing to solve it.
In the end, appeals to the multiverse ironically bolster the strength of the argument from fine-tuning. This is because the proponent of the multiverse – by the very nature of his case – is admitting that neither necessity nor chance have sufficient explanatory power to account for it. He must go beyond mere luck/necessity and postulate an imaginative solution that multiplies his probabilistic resources to the point where fine-tuning becomes inevitable. The fallacious and desperate nature of this speculation shows that there is no good alternative to the design hypothesis, which is why we hold it to be the best explanation.
Objection 6: What if the constants and quantities had to be the way they are? If their values are somehow necessary, then fine-tuning isn’t a problem that needs to be resolved or explained.
This objection amounts to burying one’s head in the sand. Physicists and cosmologists openly acknowledge that the need to explain fine-tuning is a very real problem; they also acknowledge that necessity is not the answer. Consider this recent statement from George Ellis: “Physicists’ hope has always been that the laws of nature are inevitable – that things are the way they are because there is no other way they might have been—but we have been unable to show this is true. Other options exist, too. The universe might be pure happenstance—it just turned out that way. Or things might in some sense be meant to be the way they are—purpose or intent somehow underlies existence.”10 Stephen Hawking has likewise concluded, on the basis of his work in string theory, that the constants and quantities did not have to be the way they are. He writes, “…[string theory] allows a vast landscape of possible universes…”11 Paul Davies writes, “…the physical universe does not have to be the way it is: it could have been otherwise.”12
This is reality and we have to face it squarely. The range of possible values for our universe’s physical constants and quantities is vast, and there is no prescriptive law which determines what values must be assumed. They just happen to fall into the extraordinarily narrow range of universe- and life-permitting values. The incomprehensible improbability of fine-tuning, coupled with the fact that it is not necessitated by law, leaves us stunned by its actuality. It cries out for an explanation, but neither chance nor necessity can be more plausibly affirmed than design.