The latest argument against design came from Darwin, the argument is that evolution by natural selection can explain the variety and complexity of life on earth that we used to think necessitated an intelligent designer. While this argument works in biology since life can change with every new generation, no such argument exists in the area of physics. For some time now atheist scientists have been wrestling with the apparent design of the universal constants found in physics. Universal constants like the speed of light, the gravitational constant, the weight of protons, neutrons and electrons, and the magnitude of the strong and weak nuclear forces are all exactly what they need to be for life to exist. If they deviated by one part in a million, life would not be possible. For example, if the strong nuclear force changed by 0.0001% then six protons wouldn't combine to make a stable carbon atom (required for all carbon based life). Life exists on a knife edge of universal constants.
When confronted with the incredible improbability of the universe providing the exact conditions required for life, some confuse these universal conditions with biological conditions, arguing that we evolved to suit our environment rather than our environment being designed for us. A popular version of this confusion is known as puddle theory (from the Hitchhikers Guide to the Universe). Puddle theory draws an analogy of a puddle becoming aware that the hole he occupies fits him perfectly, and so he contemplates its designer as he evaporates in the afternoon sun. However, the anthropic principle (also known as the fine-tuning argument) isn't an argument about the improbability of life existing in certain environments, it's an argument about the improbability of life existing at all. It's not the fine-tuning of life that already exists, it's the fine tuning of universal constants that are required for life to exist. Life can adapt to fit a certain environment (like a puddle in a hole), but it can't adapt from non-existence to existence. Puddle theory is an analogy for evolution, but not the anthropic principle. For puddle theory to scratch the surface of the anthropic principle, the puddle would have to become aware of something like the hydrogen bond which causes hydrogen and oxygen, which are both gases at room temperature, to combine to become a liquid (water) at room temperature.
Some have tried to use the fact that life exists on a knife edge of universal constants as an argument against design. Conceding the narrowness of the conditions for life, they argue that if the universe was designed it was an extremely inefficient design (“some design” they say) since life does not exist in the vast majority of the universe, and has not existed for the vast majority of the history of the universe. Again, this is confusing the universal conditions that make life possible in the first place, with environmental conditions like temperature, gravity and an atmosphere. Leaving this aside, their argument is against a god who is either in a hurry, or needs to be efficient (presumably because creating a big universe would be difficult), or both. If God's purpose in creating the universe was to create life on earth (especially human kind), then it is a successful design. There's simply no reason why God would have to create a universe that was smaller or younger to achieve his purpose. If God is omnipotent then creating a vast universe is not difficult for him. Unless God is impatient there's no rush to create life straight after the big bang.
Apparently the strongest counter argument against the anthropic principle is the multiverse theory: that there are as many universes as there are combinations of universal constants and we just happen to be in one where the constants are what they need to be for life to exist. Most atheist scientists put this forward as if it doesn't require more faith than intelligent design. Some even claim to have evidence for other universes from satellite pictures and measurements, however they are claiming to observe a universe that exists outside of our universe, from observations that are made from within our universe. In order to observe other universes, you would have to somehow be outside of our universe, unless this was a closed universe with a window at the end that allows us to see what's outside of our universe.
What's more disturbing is the lack of science in this theory that's put forward as scientific. Science begins with observation from which hypotheses are made and then tested. The multiverse theory did not begin with observation, it was proposed as a theory which then led to a search for observation (which has not found anything). Furthermore, there is no scientific way to test the multiverse theory, no experiments to test the theory have even been proposed let alone carried out. Without any scientific beginning or any scientific way forward, this is nothing more than a philosophical speculation disguised as a scientific theory. If there was a single shred of evidence for the multiverse it would have the potential to be a scientific theory, but until then it remains a convoluted speculation (which should really be discarded by Occam's razor), proposed in order to justify the rejection of an intelligent designer whom atheists would prefer didn't exist.
