Christians base their interest in God virtually entirely on the following argument.

If the Universe evinces purposeful design, there must have been a designer.

The Universe does evince purposeful design.

Thus, the Universe must have had a designer.

Nobody really likes the argument that God is the answer to why there is something rather than nothing.  It sounds too remote or uninteresting.  They prefer to look around and imagine they see the handiwork of God.

But what if you argue:

If the Universe evinces traits of non-design, there is no Designer.

The Universe does evince non-design.

Thus, the Universe had no Designer.

People think they have to choose one or the other.

What if we say the universe has some signs of design and some signs of non-design? What if the universe shows more chaos than design? Then the argument may show there is one or more designers yes but they are not involved in looking after the whole universe. The non-designed stuff is out of their reach.  The argument is no good at showing there might be a God.  The believers lie that it shows there is a God. That is an outright lie.

Another problem is that design does not mean the design is purposeful.  If the designer is something like a computer intelligence it just designs and does not have any purpose.  Believers argue that you can observe the universe and not see that the design has a purpose.  True but what if you are failing to observe that any design in fact has no purpose?
Marcus Chown says,

We associate the direction of time with the direction in which eggs break, castles crumble and people grow old. What all these changes have in common is a transition from an ordered to a disordered state. Technically, physicists call this an increase in “entropy”.
The reason things can become more disordered is obviously that they were more ordered in the past. And, if we follow this reasoning to its logical conclusion, we find that the ultimate reason is that the universe began in a highly ordered state – the Big Bang. Think for a moment what this means. Eggs break, castles crumble and babies grow old because the universe is expanding from a Big Bang – because the most distant galaxies are flying away from us. How incredible is that?

I say,

Believers in intelligent design seem to think that a fully fledged universe appeared at the big bang! No wonder they feel the need to believe in intelligent design. They forget that most of the universe even now is chaotic and unorganised.

It is possible that something can work well enough without being designed. Religion says an intelligent designer is needed. But needed is too strong of a word. It is not needed. Are they guilty of saying, that things always need to be designed before they can do anything?  Things work well despite their design diminishing.

Take design as meaning something looks like the work of an intelligence.  The entity that existed "before" the big bang is regarded as well-designed in its own way.  There was not really a big bang.  It was several big bangs - probably an infinity of them.  The end result as good as it looks was not as well-designed as the original entity.  So the universe means there is less design not more.  What use is the design argument when loads of accidental big bangs had to happen for the universe to be possible?  The accidents actually count more.
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