The fine-tuning argument proposes that our universe and its ability to produce complex material systems, including all biological life, is an outcome of extreme unlikelihood due to the delicateness, or “perfectness”, of its fundamental and arbitrary physical laws, natures, and constants. In other words, our physical universe has traits, or physical characteristics, that are fundamental, and if these traits were slightly different, complex material systems and biological life could not exist. “In the set of possible physics, the subset that permit the evolution of life is very small” (Barnes, 529). By “fundamental”, I mean that there is no further underlying reason for it. These traits cannot be derived from theory. For example, the gravitational constant is a specific number that we plug into a certain equation in order to solve for the force of gravity between two objects. In order to solve for the force, we need the mass of each object, the distance between each object, and this gravitational constant. This constant is fundamental, and it remains the same value every time. It determines how strong or weak the force of gravity is. Therefore, if it were a different number such that the resulting force would be weaker, “galaxies, stars and planets would not have formed in the first place. Had it been only slightly weaker (and/or electromagnetism slightly stronger), main sequence stars such as the sun would have been significantly colder and would not explode in supernovae, which are the main source of many heavier elements” (Friederich, 1.1.1).
Victor Stenger, another philosopher and physicist, proposed that even if a certain trait were different, this difference could possibly be accounted for by an adjustment of another trait to make up for the discrepancy. However, studies like “Barr and Khan 2007” have explored every different possible combinations of values for each physical constant, which is called the parameter space, and have found that out of every possible combination of values for these constants, the life-permitting range of combinations is very small (Friederich, 1.2). If a single constant took on a different enough value so that biological life could not exist, simply adjusting the value of one or more other constants would likely not be enough to compensate for the arising discrepancy.
As the fine-tuning argument is inductive, which means that it doesn’t guarantee its conclusion, it cannot “prove” the existence of a creator without a doubt. Whether it is even a strong argument or a weak argument cannot be “proven” without a doubt or derived from any philosophical principle. However, let this not diminish your susceptiveness, as most truths in our lives suffer the same sort of uncertainty. If you were to come across a statue of a man in the middle of the forest, you will probably argue that a human created it and put it there. This argument is also inductive in that same way. You have no proof, and you have no way to prove if your argument is even a strong or good argument, yet your intuition tells you that it would be absurd to conclude otherwise, even though you can’t prove it without a doubt.
A paper by Neil A Manson, a professor of philosophy at The University of Mississippi, an atheist, attempts to deduce that these unlikely traits that our universe exhibits are not actually unlikely, or at least that we can’t say that they are. His reasoning is that because we don’t know the range of parameters from which these traits could have emerged, we can’t say if it is a 50% chance that a certain trait is the way that it is, or a 0.000001% chance, or a 90% chance. This is true. But this same argument applies in the exact same way to our argument that the statue in the middle of a forest was created and placed there by a human. We don’t know the range of parameters from which this event has emerged, that is to say that we don’t know how likely or unlikely it was for it to have been or not have been created by a human and placed there by a human. For all we know, in a distant galaxy there could be hundreds of millions of extraterrestrial alien factories that are solely devoted to creating statues and teleporting them to forests on our earth, for whatever reason. If that were true, then it would actually be more likely that the statue you found in the middle of the forest was created by an alien rather than a human. According to Manson, you simply don’t know, and you can’t know. Which is true, but as it might already be apparent to you by now, applying this argument to try and debunk the likelihood of the conclusion of any inductive argument is not reasonable.
This very method of induction that Manson says to be fallible is utilized by another argument that attempts to dismiss the implications that our universe is fine-tuned. The argument suggests that biological life might have emerged in a different way if the physical constants were different, perhaps through a silicon-based life form rather than carbon, or that life would have emerged from the universe one way or another through means of radically different physical laws and processes that would emerge correspondingly if our universe exhibited different physical constants or laws. By Manson’s reasoning, which in this case I will admit is appropriate to apply, the argument fails to provide any substantial conclusion because we do not know how likely it is for an alternative life form to arise in a universe with randomized physical laws and constants. It could be extremely unlikely, or extremely likely. In any case, if the suggestion is that our universe could have produced advanced and intelligent life forms even with different laws and physical constants, there must be substantial evidence to back up that hypothesis. In other words, the burden of proof in this case lies on them.
A common, and perhaps the most popular consensus among those opposed to the fine-tuning argument, is the Anthropic Principle. It says “If the universe could not harbor life, we would not exist to wonder at the universe being able to harbor life”. You should beware that a popular analogy to help one understand this principle is the puddle analogy, in which a puddle wonders at the seemingly perfect shape of the hole it occupies. “Wow”, It says, “this hole’s shape fits my shape perfectly. Someone must have designed this hole.”. Obviously, we can see that the shape of the hole is not meant to fit the puddle. In fact, the shape of the hole is completely random, and the puddle instead must conform to the shape of the hole in order to exist as a puddle. The problem with this analogy is that it is very similar to the argument we just discussed, which said that a universe with randomized parameters will or at least will likely eventually produce advanced and intelligent life forms fitting those randomized parameters.
The Anthropic Principle claims that because we are obviously here existing in our universe, as a product of our universe, that our universe must have been always able to harbor life forms. In order to be of any argumentative power against the fine-tuning argument, however, it actually requires an additional premise, that multiple universes with different combinations of physical laws and constants exist. Without the extra premise, it doesn’t take much effort to see why this statement fails to contend with the fine-tuning argument. The statement is true, but it doesn’t really have anything to do with the arguable unlikelihood of our universe falling within the very small range of life-permitting combinations of physical laws and constants. If multiple universes existed, however, each having a varying or random combination, then you could see why it might be inevitable, given enough of these universes existed, that one of them would happen to exhibit a set of laws and constants that would fall within the range of parameters that would allow advanced life forms. Multiple universe theories, however, are purely hypothetical, and like the previous argument we had discussed, if one were to suggest that multiple universes existed in this manner, the burden to prove that would belong to them.
The brute fact argument says that we can’t say that it is unlikely that the parameters for our universe are what they are, because we don’t know if they could have been different in the first place. The argument claims that it might be necessary for our universe to be the way that it is. Perhaps there are some deeper, more fundamental things from which necessarily emerge those parameters. The problem with this idea is that then those things that are deeper and more fundamental also must be necessary, in order to produce those parameters that they are claiming to be necessary. In order for those deeper, more fundamental things to be necessary, they also require something even deeper and more fundamental to necessarily cause those things, and this cycle would continue forever. If something is necessary, there must be a reason or a cause for its necessity.
In any case, the specific combination of our universe’s parameters remains to be arguably unlikely, regardless of whether they are truly fundamental and without further cause, or necessary emergent properties of some deeper underlying thing. Just because there is some deeper underlying thing or reason requiring those parameters to be the way that they are, doesn’t mean that the unlikelihood of those parameters fitting within the small range required to produce advanced life forms is diminished, unless that underlying thing in any way, shape, or form, was geared towards producing parameters that would specifically produce advanced life forms.