How many times have you heard the claim that the fact that the universe is "fine tuned for life," is evidence enough for a designer?
It's a strange notion honestly, the idea that the universe was designed for life, but for some it brings solace. Truthfully, if that's all you want out of that thought, and are content there without further question, then more power to you. However, for most people who buy into this account, that is not their only ambition for thinking in such a manner. They intend on forcing their god(s) into that gap and converting non believers via this tactic, and for me that is reason enough to discuss this matter and present the opposing, logical (at least in my mind), stance on the issue.
So let's take a deeper look at the idea of a finely tuned universe.
We'll start with the region of the universe we are most familiar with, our solar system. Our Sun is the local star and the center of our particular solar system. By any standard it is a modest star, not too big, not too small, not too hot, etc... However, the Sun's mass makes up more than 99% of the mass in our solar system.
Let that sink in.
All of the planets in our solar system combined amount to a quaint 0.135% of our solar systems mass with about half of that being Jupiter.
So we've established here that the Earth is a vanishingly small amount of the total mass in our own neighborhood and as far as we know, we're the only life in the solar system at the moment. This means that over 99% of the mass in our solar system is uninhabitable for life as we know it. But let's look at Earth. I'm going to over look the fact the the majority of the times when this topic is brought up the life the believer is talking about is man, I think you can see where I'm going with that. So I'm going to give them the benefit of the doubt and extend that definition to include all life as we know it. Now the Earth boasts a mass of 5.9742 × 1021 tonnes with roughly 1,877 billion tonnes of it measured as biomass (organic life). You're math doesn't have to be great to see that we are, in effect, equivalent to a film on the surface of our planet.
Some people will read that (or have read it ) and say it's a depressing world view, the idea we are so small on the cosmic scale of things, however I find it invigorating. But I'll come back to that. The only point I'm attempting at here is that our solar system is not what any decent engineer would design if he was attempting to "fine tune," an area for life. In fact, I would venture to say, it is woefully inefficient in that regard.
Now when we consider that our solar system is, once again, a modest solar system in our own Milky Way Galaxy which is home to more than 100 billion such systems, and when we consider further that our galaxy is just one of more than 100 billion other galaxies, each home to still another 100 billion systems, perhaps we begin to understand a bit more just how rare indeed we are. This is even if we assume that life happens once per solar system, which there is no reason to assume that at all. Even if it were the case though, life would still be less than a smudge in the grand scheme of things.
Most of the universe is a harsh and unforgiving territory that is completely inhospitable to life as we know it, hardly the "finely tuned for life," place one would imagine if it was designed by an omnipotent, omniscient being.
Now some apologists will tell you that they are merely speaking in regards to exactly how precise the four fundamental forces must be in order for life to exist. These forces being electromagnetism, gravity, the Strong nuclear force, and the weak nuclear force.
In that sense they are correct, without these four fundamental forces having their very specific values, life as we know it would not be possible. There is still, understandably, much debate on just how much variation can still produce a so called "biophilic universe" such as the one we live in. However, there is no mistaking that with even the slightest change in one of these four fundamental values we would see a vastly different universe than what we have today.
This is an interesting train of thought, however, it leads me to my next point. If it is the case that only these very specific values for the four fundamental forces can produce a universe in which life is possible does it not raise the question, did god have a choice in how to create the universe if he intended it to bear life?
What I mean here is that if ONLY these very specific values will combine to make life possible, then god had no choice but to make the universe in the way he did (this is of course assuming that a god did, in fact, create the universe). This brings into play a paradox, an omnipotent being would not have such constraints.
The idea I'm pointing at is this, how come life as we know it only happens in places that science predicts it would appear? I would be much more inclined to believe in an all powerful creator if the Earth's orbit was outside that of Saturn's, or perhaps inside that of Mercury's yet it still teemed with life. This would be the mark of an all powerful, supernatural deity.
Instead, for whatever reason, our universe seems to operate much like one that came into existence spontaneously after a brief period of very rapid inflation came to an end. We have excellent predictive models that demonstrate this fact and yet, none of these models need god to balance the equations.
Here I'm reminded of Pierre-Simon Laplace when Napoleon asked him why his model of the solar system did not include god,"Je n'avais pas besoin de cette hypothèse-là!" (roughly, I did not need to make such an assumption.)
As I mentioned above, I don't view any of this as a pessimistic take on things at all. In fact, I believe it to be quite the opposite. This sort of worldview affords the opportunity to not only have a deeper understanding of our universe and its mechanics but also our origins, the stars. It allows us to see (and appreciate) a deep rooted connectivity that we share with the entire universe, every atom in our body is the echo of a cosmic event that happened 13.7 billion years ago. Every element in our being was forged in an ancient generation of stars that exploded violently and seeded our universe with the raw material needed to build each one of us.
We are all connected to the universe, in fact I would say, we are the universe, an assembly of matter and energy that has, over the course of 13 billion years, become aware of itself. You might say we are the universe experiencing itself. From this take we can see a picture of the universe where hurting another person, or condemning them to eternal torture is madness for you are only hurting yourself, truly. In a worldview that shows a deep seeded connectivity to everything around us, why would we partake in such self destructive insanity?
I'm getting a bit off topic so suffice it to say, this is hardly a pessimistic way of seeing the world.
Ultimately, the idea that our universe was fine tuned by an omnipotent, omniscient being is hardly optimistic (being that generally said deity turns out to be a bit of a tyrant), and certainly is not supported by any sort of empirical evidence. Any engineer that would design an area in which less than 1% of the mass in the area is going to be used for the purpose he was designing it for would be fired.