Life from non-life
Life is complicated and its origins are even more complicated. Once upon a time people thought that our cells were just squishy building blocks. We now know that they are frightfully complex and within they contain our genetic code, the information that determines everything about us. Explaining where this came from a tricky problem. (This is not about evolution – that’s the process by which a species changes over time due to natural selection. This is about how life got going in the first place).
DNA (deoxyribonucleic acid) is a complex chemical, consisting of two chemical chains closely linked together and then twisted round each other, making a single long twisted strand. The chemical chains themselves can be made up of different components. Sets of three components (bases) define what the chemical 'letter' actually is, and other biochemicals recognise these triplets as different. The sequence of these letters makes up the DNA, much like a computer program.
Human DNA has about 3 billion letters. Other forms of life have shorter codes. Scientists presume that the first life-form must have had something shorter still. Even so, we are still talking about a substantial amount of genetic code and it is difficult to think how this could have been produced by chance.
Let us consider the possibility of getting a single sonnet of Shakespeare by random means. A sonnet has a typical length of 488 letters. Since there are 26 letters in the English alphabet, then the possibility of a sonnet occurring by chance is 26 times itself 488 times. This is one chance in 10690. The number of particles in the universe is 1080. So even if all the particles in the universe were random sequences of 488 letters of the English alphabet, there are not enough particles for a single sonnet to occur by chance. That is problem facing scientists as they try to explain the origin of life – how could DNA have occurred naturally if it is not possible for it to have occurred by chance?
Explanations of the origin of life
But there does seem to be a ready explanation. Whenever we find information we infer the existence of a mind. For example, a computer program indicates the existence of a computer programmer, a book indicates the existence of an author and a message beamed to us from another planet would indicate the existence of alien life. So the fact that there is information in our cells should lead us to conclude that there was a Designer. The point is not that scientists have not yet come up with a natural explanation for life (and they haven't); the point is that the presence of information in our cells is strong evidence of design.
Alternative explanations for the origin of life do not seem very compelling. The earth is only 4.5 billion years old – not enough time to make chance collision of chemicals a credible explanation for life. One might try to reduce the odds a bit, but it is not clear how one can reduce the odds enough to make chance seem plausible. The other alternative is necessity but to say that the universe is set up in such a way to make the origin of life inevitable sounds a lot like fine tuning, which again would point to design.
God remains the best available explanation.