Our world is a beautiful place, naturally speaking. Anybody who has walked the Serengeti or has wrapped their arms around a Redwood tree or has looked at a snowy mountain from afar or has gone scuba diving in an ocean knows this. The world is an incredible place teeming with "endless forms most beautiful and wonderful".
The natural world can be so breathtaking in fact, that a single person, in awe of their own smallness in the midst of such grandeur, can feel that this beauty must be by design. Such a feeling is perfectly normal. How can one look at the Great Barrier Reef, or the multicolored-squiggles on the body of a Mandarin fish, or the speed of a hummingbird's wings, or the spots on a giraffe, or the spellbinding glow of lava pouring from a volcano, and not conclude that the world isn't one big lovely painting? And doesn't a painting require a painter?
This is what is often expressed by religious believers who encounter the splendor of nature.
But there is a problem with viewing the world strictly through the lens of its beauty. As the famed BBC nature documentary broadcaster David Attenborough once noted, "People sometimes say to me 'Why don't you admit that the hummingbird, the butterfly, the Bird of Paradise are proof of a wonderful creator?' And I always say 'Well, when you say that, you've also got to think of a little boy sitting on a river bank in West Africa that's got a little worm, a living organism, in his eye and boring through the eyeball and slowly turning him blind. The creator you believe in, presumably, also made that little worm. Now I personally find that hard to reconcile with the notion of a divine and benevolent creator.'"
This brings to mind a moment in college where a Christian sorority girl I once knew (who was a bit on the bubbly side) asked me, "How can you look at a pretty sunset and tell me there is no god?" And my reply, after a few moments of stunned silence staring at the Gwyneth Paltrow of Theology, was "Because every day that sun sets on a starving child, a dead teenager in an automobile accident, a house on fire, a battered wife, and a person with terminal cancer. And every day, while you remain fascinated by one 'pretty sunset', billions of other similar suns in the universe flicker out and die. That's how I can tell you there is no god." She never spoke to me again.
As it is with every idea, some expressions of the same opinion are more sophisticated than others. The best that the sorority girl could offer up was a pretty sunset in defense of her belief that the world— and the universe— was made by design. But other religious believers have offered much more detailed arguments, like the "fine-tuning" argument offered up by the Discovery Institute (and many, many Christian apologists before them):
First, if the initial explosion of the big bang had differed in strength by as little as 1 part in 1060, the universe would have either quickly collapsed back on itself, or expanded too rapidly for stars to form. In either case, life would be impossible. Second, calculations indicate that if the strong nuclear force, the force that binds protons and neutrons together in an atom, had been stronger or weaker by as little as 5%, life would be impossible. Third, calculations by Brandon Carter show that if gravity had been stronger or weaker by 1 part in 10 to the 40th power, then life-sustaining stars like the sun could not exist. This would most likely make life impossible. Fourth, if the neutron were not about 1.001 times the mass of the proton, all protons would have decayed into neutrons or all neutrons would have decayed into protons, and thus life would not be possible. Fifth, if the electromagnetic force were slightly stronger or weaker, life would be impossible, for a variety of different reasons.
Imaginatively, one could think of each instance of fine-tuning as a radio dial: unless all the dials are set exactly right, life would be impossible. Or, one could think of the initial conditions of the universe and the fundamental parameters of physics as a dart board that fills the whole galaxy, and the conditions necessary for life to exist as a small one-foot wide target: unless the dart hits the target, life would be impossible. The fact that the dials are perfectly set, or the dart has hit the target, strongly suggests that someone set the dials or aimed the dart, for it seems enormously improbable that such a coincidence could have happened by chance.
What we're supposed to conclude from this, of course, is that because conditions in the universe are "tuned just right" for life to exist, there must be a creator/designer/god.
But, respectfully, this isn't the "gotcha" that religious people think it is.
Yes the calculations are all correct. If the strength of the big bang had differed slightly, the universe would have either collapsed in on itself or expanded too rapidly. If the nuclear force that binds protons and neutrons together had been stronger or weaker by 5%, life couldn't happen. If the strength of gravity was altered in the slightest, there wouldn't be stars or galaxies. The problem with the argument is not the calculations. The calculations are correct. The problem with the argument is that it starts with the presupposition that life was the goal of the universe's development, and it assumes that both naturalism and theism operate from that same assumption when they try to explain the universe. If this were the case, naturalism would look quite silly. But that's just the thing... naturalism does not hold that life was the goal of the universe's development. Rather, life was a mere byproduct that occurred because of the way the universe developed.
Do you see the difference and what that does to the whole "fine-tuning" argument?
In other words, whereas the theist looks at gravity being just strong enough for the stars and galaxies to develop, and says "See! Gravity had to be 'tuned' to be the strength that it was, in order for there to be stars and galaxies so that life could begin!", the naturalist would quite reasonably respond "No, the strength of gravity simply became what it was, and as a result galaxies and stars formed, and because of that, life eventually happened."
In a nutshell, theism speaks of the Effect as if it were the "reason for" (or "purpose of") the Cause developing the way it did, where the naturalist simply says the Effect happened because the Cause developed the way it did.
So when somebody tells me that the odds of things in the universe developing "just right" for life to begin are slim-to-none without a designer, my response is simply that without a designer there are no "odds" and there is no "just right". Because life is not a predetermined outcome if there's no one there at the beginning of the universe to make that determination. It's just a byproduct out of many byproducts that are the result of a random process, and we're only "conditioned" to see life as something intrinsically unique and special because it's essential to our existence.
And that's my main rebuttal of the "fine-tuning" argument.
There are other ways to refute the "fine-tuning" argument of course. For instance, the fact that those who argue for the fine-tuning of the universe for life are only considering the universe as it is in the present moment. Consider the first 2 billion years of our earth's lifetime, when it was merely a hot ball of volcanic gas with no atmosphere and certainly not hospitable to any life form (a period known as the Hadean and Archean eons). Or consider further the fact that an asteroid could wipe out life on our planet at any moment (do "fine-tuners" ever wonder how a designer managed to get the nuclear force that binds protons and neutrons "just right", but didn't think in the course of his/her creating stuff that asteroids would be a problem?)
You might be thinking at this moment, "So what? I mean, why spend time refuting the 'fine-tuning' argument? What are you trying to achieve?" And indeed this is a very good question, because I think you and I both know that even if believers in god were to recognize that the "fine-tuning" argument was rubbish, they would still continue believing in god, just as atheists would still find a way not to believe, pretending for a moment that the argument was stronger than it is. Both camps are typically entrenched pretty firmly (and I certainly am not a neutral observer to this, as you've probably gathered).
So my ultimate purpose for taking on "fine-tuning" has not been to persuade religious people to stop being religious. Even during my very brief (and admittedly somewhat rude) exchange with the Christian sorority girl— to revisit that moment again for the last time— I didn't entertain for a moment that my response to her "sunset" challenge would change her mind so much as make her want to slap me. I find that when it comes to deep convictions— while good arguments do go a long way— nothing will change the person except the person themselves.
My goal, rather, in taking apart the "fine-tuning" argument is ultimately to persuade believers that secular conceptions of the universe can be just as awe-inspiring (and in my opinion more awe-inspiring) as the belief that the universe was planned with us in mind (and I didn't feel I could really make this point if I had left the "fine tuning" argument in place). For me, the accident of life is actually more striking in a positive way than its alleged design. Because beautiful things happen by accident all of the time and sometimes that adds to the beauty.
There is one analogy that comes to mind that, to me, illustrates this point: Two strangers meet at a grocery store, and due to some circumstance or other, they strike up a conversation at checkout and find that they are both intensely drawn to each other. They swap numbers and eventually wind up becoming a couple. Years later this couple might look back and think with terror about how different their lives would have been had the man decided he didn't need milk that day or had the woman chosen not to go get eggs.
What makes a situation like this as pleasantly fascinating as it is, is that there is no plan involved. So much of our lives— including our romances and careers and interests and acquired tastes— are the result of misadventures, detours, accidents, sudden changes of heart, "being at the right place", and dumb luck as opposed to deliberate orchestration.
The secular man and woman looks at nature and the universe much the same way. That everything from the Amazon to the cosmos is stunning in its beauty, resilience, tranquility, or even in its frequent violence and barbarity, is accentuated all the more for us by the perception that it is the one outcome that happened out of the many other possible— much more dismal— outcomes that didn't.
To conclude, the best things in life— from your first taste of lemon and your first kiss to your first time living on your own and your first time having a go with the opposite sex, and everything in between, like good music, good food, good friends, good art, good travel, good scents, even the moments of sadness and heartbreak— take on far more sweetness when you consider the fact that none of it was "supposed" to happen at all, and things could easily have happened differently.
When we recognize that existence is a wonderful wonderful one-in-a-million fluke, we realize also in that same moment why it's such a treat. I propose a reversal of Pascal's Wager: I cannot be certain, or even close to certain, that there is a life waiting for me after this one; let alone one where the streets "are paved with gold" (according to Revelation 21:21) or "have no name" (according to Bono). But what I can be 100% certain of is the life I am living right now. Thus it seems I risk a colossal waste if I follow the restrictions of any religion (out of hundreds) which claims to know perfectly the will of an unproven designer. The better wager appears to be to make the most of life by enjoying it. To take bold risks, speak my mind honestly, seek out wisdom and opportunities for travel, make time for humor and other pleasures, and love as if there is no life after this one.
As Phil Zuckerman said in his book Living The Secular Life:
This mostly wet ball full of ptarmigans, ponytails, and poverty is floating in space among a billion other balls, and there are galaxies swirling and there is a universe expanding, which itself may actually just be an undulating freckle on the cusp of something we can't even conceive of, amid an endless soup of ever more unfathomables. And I find such a situation to be utterly, manifestly, psychedelically amazing— and far more spine-tinglingly awe-inspiring than any story I've ever read in the Bible, the Qur'an, the Vedas, the Upanishads, Dianetics, the Doctrine and Covenants, or the Tibetan Book of the Dead. So smell that satchel of tangerines and nimbly hammer a dulcimer or pluck a chicken and listen to your conscience or master a new algorithm or walk to work or hitch a ride. Because we're here. And we will never, ever know why or exactly how this all came about. That's the situation. Deal with it. Let the mystery be.