Design vs. Chance This universe and more specifically, this earth is set to the exact conditions needed to sustain life. Any change one way or another would destroy all life on planet earth.
Here are some examples:
The Earth: Its size is perfect. The Earth's size and corresponding gravity holds a thin layer of mostly nitrogen and oxygen gases, only extending about 50 miles above the Earth's surface. If Earth were smaller, an atmosphere would be impossible, like the planet Mercury. If Earth were larger, its atmosphere would contain free hydrogen, like Jupiter. Earth is the only known planet equipped with an atmosphere of the right mixture of gases to sustain plant, animal and human life.
The Earth is located the right distance from the sun. Consider the temperature swings we encounter, roughly -30 degrees to +120 degrees. If the Earth were any further away from the sun, we would all freeze. Any closer and we would burn up. Even a fractional variance in the Earth's position to the sun would make life on Earth impossible. The Earth remains this perfect distance from the sun while it rotates around the sun at a speed of nearly 67,000 mph. It is also rotating on its axis, allowing the entire surface of the Earth to be properly warmed and cooled every day.
And our moon is the perfect size and distance from the Earth for its gravitational pull. The moon creates important ocean tides and movement so ocean waters do not stagnate, and yet it restrains our massive oceans from spilling over across the continents.5
Water: It’s colorless, odorless and without taste, and yet no living thing can survive without it. Plants, animals and human beings consist mostly of water (about two-thirds of the human body is water). You'll see why the characteristics of water are uniquely suited to life:
• It has an unusually high boiling point and freezing point. Water allows us to live in an environment of fluctuating temperature changes, while keeping our bodies a steady 98.6 degrees.
• Water is a universal solvent. This property of water means that thousands of chemicals, minerals and nutrients can be carried throughout our bodies and into the smallest blood vessels.
• Water is also chemically inert. Without affecting the makeup of the substances it carries, water enables food, medicines and minerals to be absorbed and used by the body.
• Water has a unique surface tension. Water in plants can therefore flow upward against gravity, bringing life-giving water and nutrients to the top of even the tallest trees.
• Water freezes from the top down and floats, so fish can live in the winter.
Ninety-seven percent of the Earth's water is in the oceans. But on our Earth, there is a system designed which removes salt from the water and then distributes that water throughout the globe. Evaporation takes the ocean waters, leaving the salt, and forms clouds which are easily moved by the wind to disperse water over the land, for vegetation, animals and people. It is a system of purification and supply that sustains life on this planet, a system of recycled and reused water.7
The Human Brain: simultaneously processes an amazing amount of information. Your brain takes in all the colors and objects you see, the temperature around you, the pressure of your feet against the floor, the sounds around you, the dryness of your mouth, even the texture of this article in your hand. Your brain registers emotional responses, thoughts and memories. At the same time your brain keeps track of the ongoing functions of your body like your breathing pattern, eyelid movement, hunger and movement of the muscles in your hands.
The human brain processes more than a million messages a second.8 Your brain weighs the importance of all this data, filtering out the relatively unimportant. This screening function is what allows you to focus and operate effectively in your world. A brain that deals with more than a million pieces of information every second, while evaluating its importance and allowing you to act on the most pertinent information...can we say mere chance brought about such an astounding organ?
Consider for a moment an illustration:
Imagine that you were on an Amtrak train that was headed for Baltimore. While on the rain, you look out the window and notice that some rocks on the side of a hill spell out “Amtrak Welcomes You To Baltimore”. How do you assume that they got on the side of that hill to spell that message?
A.They fell from the sky and landed in that exact place.
B.They rolled down the hill over time to exactly that place with no help from an intelligent being (man or god).
C.They were placed there by some men to communicate a welcoming message to people who see it by Amtrak. Any intelligent person would find it most rational to believe that the message was placed there by men.
However, let’s say that I believe that they did indeed roll down the hill over time by chance and ended up in that exact location. This is definitely possible (although not likely) that these stones could have rolled down the hill to that position. The chances would be through the roof that they would do that, but it is still possible. While this is a position that is difficult to accept, it would be infinitely more bizarre for me to believe, solely on the evidence provided by the stones that I was actually entering Baltimore !!! If, I suppose that the stones might have come to that arrangement accidentally, over the course of time, simply by rolling down the hill, one by one, and finally just happening to end up that way, or if they were strewn upon the ground that way by the forces of any earthquake or storm or what-not, then my argument would in no sense constitute evidence that I was actually entering Baltimore, or anything at all connected with that message is true because the message was simply brought about by chance. It has no way of communicating anything at all if it was the result of random accidental chance over time. Just like it is possible for a collection of stones to present an intelligible message on the side of a hill over time, so also it is possible for such things as our cells, organs, and mind to be the accidental, unintended result, over ages of time, of impersonal, non-purposeful chance. However, even if one does believe that our bodies did come about by chance, it is irrational for one to say that your mind, emotions, and thoughts reveal any truth about the world with respect to themselves. If your body is a result of chance, then your mind is as well. So, any message your mind may communicate to you would be just as non-purposeful and random as the process that brought it about. Without God, there is no way to believe in truth or logic.