Design arguments used to be very popular. From ancient Greek philosophers to medieval Islamic scholars to Victorian country pastors, almost everybody thought that lots of things in nature were clearly designed and therefore there must be a Designer.
Nowadays design arguments have got a lot of bad press. This is, in part, due to some very sloppy design arguments (e.g. “I don’t know how this works, therefore God did it”) – unfortunately silly people get more attention than the sensible ones.
The other reason design arguments are no longer in vogue is because we now realise that some things can appear very complex and yet not be designed. The most famous example is Charles Darwin’s theory of evolution. Darwin realised that just as farmers can breed healthier and more productive livestock, so natural events can determine which animals survive and, over time, shape the genetic traits of a species. The fact that natural processes can produce the appearance of design has made people rightly cautious of using design arguments.
However, despite this caution, there remain three basic types of explanation: necessity, chance and design.
- By necessity we mean things that are conditioned by circumstances, like natural laws. For example, if you drop a ball it will fall to the ground – not by design, but because of the law of gravity.
- By chance we mean things that are the unintended consequence of other processes. For example, a man might go to the shops to buy some eggs and, by chance, meet the girl of his dreams.
- By design we mean things that are caused intentionally by an agent, such as an engineer designing a car.
The key question is: how do you distinguish things that are designed from things that happen by chance or by necessity?
The answer is specified complexity. By complexity we mean that there are many different options of how something could have turned out. If something is necessary then there is only one thing that can happen (e.g. the ball will fall to the ground) so if something is very complex then it is unlikely to be the product of necessity. By specificity we mean that of the many different options, the thing that happened was very significant. Think about your computer password; it is complex (there are lots of different options) but it is also specified (only one password unlocks the computer). Imagine I sat down at your computer, typed in a password and got the right one first time. You would not think outcome was the result of necessity or chance, but you would assume that I had stolen your password (i.e. design).
When looking for examples of design in nature, if we can identify specified complexity then it will be a good indication of design. This means looking for things that are very unlikely (complexity) but also very significant (specified). In the next sections we will look at the fine-tuning of the universe and the origins of life. In both cases we will see that these phenomena exhibit specified complexity and so are likely to be designed.