Conveniently summarised by various sources, the good riddance post of Paley's watch:
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VonDavis said:
When you look at a watch, you know that a watchmaker must have created the watch, when you look at a software program you know that there must also be a programmer....just as everything in this world has a creator, a composer, a maker or an author, it is suffice to say that some super intelligent omnipotent entity must have created the entire universe... this entity is what we call God. Hence the fundamental reason for God's existence is that He is the author, the Composer of everything.....the galaxies the Sun and everything that encompasses the heavens.
After all can u look at a building n say that it was created by itself? That a telescope was created by itself....just as everything has an author.....God is the author of the universe...
That argument was ripped to pieces by David Hume a long, long time ago my friend. He killed that off with the following criticisms:
1. It assumes too much
Inferring an effect - a cosmic design - from a cause - the beginning of the cosmos is basically assuming what the argument wants to prove. Order and regularity do not imply design, supernatural or otherwise.
2.The universe is unique
It cannot be inferred that there is anything like a designer behind it; where is the undesigned universe by which one can make comparisons?
3. Who designed the designer?
If functional complexity requires a designer, then the designer also needs a designer, because the designer must be at least as complex as the thing it designed. How else could it have designed the Universe?
4. The universe shows just as much evidence of imperfection and disorder
Seeking a cause of the order when such order only partially represents what the universe is like is asking for trouble. If an all-perfect, all-good designer made the universe, why is it so full of suffering for life forms? Even if one could infer a designer from the world, there is no reason to suppose that it is the Judaeo-Christian or Islamic god. In fact, there are reasons to suppose it is not.
The perceived design in nature is not necessarily intelligent by definition. Life is the result of the mindless design and repetition of natural selection. Order in the cosmos comes from natural regularity.
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The argument is known as (Paley's) Watchmaker Argument. Here it is refuted again by another source, just in case you weren't convinced with that one.
The argument is wrong for several reasons:
1. Contradiction
The argument first assumes that a watch is different from nature, which is uncomplicated and random. It then states that since the universe is so complicated, complex, and ordered it too must have a creator. Thus, the argument gives the universe two incompatible qualities.
2. Shoemakers
What if you went further down the beach and found a shoe. Would you assume that a watchmaker made that shoe? Of course not, you would assume a shoemaker. Therefore, according to the analogy, created life must have a lifemaker, the sun a sunmaker and snowflakes a snowmaker. This implies that there are several creators in the world, responsible for all kinds of creation.
3. The watchmaker's father
Just like all watches have watchmakers, so do all watchmakers have fathers. Therefore, with the watchmaker anology, god has a father. Who is the father of god? and who is the father of the father? etc... This leads to an endless series, and the only way to end the series is to say that the original god just is without an origin and a cause. What then stops us from making the same assumption of the universe or Ultimate Reality? Occam's razor should even encourage us to do so!
4. Watches out of nothing?
The things used by the watchmaker to make watches already exists, but the theists claim that their god created things ex nihilo, from nothing. So the analogy is false here too.
5. False analogy, again
The watchmaker is a false analogy because it assumes that because two objects share one common quality, they must have another quality in common.
i. A watch is complex
ii. A watch has a watchmaker
iii. The universe is also complex
iv. Therefore the universe has a watchmaker
The last step is wrong, because it concludes something that is not supported by the criteria. It is best clearified by another example:
i. Leaves are complex cellulose structures
ii. Leaves grow on trees
iii. Money bills are also complex cellulose structures
iv. Therefore money grow on trees