The classic statement of the teleological argument is that of William Paley in his Natural Theology. Paley likened the universe to a watch. Like a watch, he said, the universe consists of many complex parts functioning in harmony towards some useful end. In a watch the various parts are ordered such that they measure time; in the universe, such that they support life. The two are, in this respect, similar. This comparison forms the basis of Paley’s argument for intelligent design.

In the case of a watch we take these properties to constitute evidence of design. If we were to stumble across a watch in a natural environment, lying on a heath, to cite Paley’s example, then we would instantly know, because of its order and complexity, that it was designed. Order and complexity are the marks of design.

If order and complexity constitute evidence of design in the case of a watch, though, then they must also constitute evidence of design in the case of the universe. The case of the watch thus illustrates the fact that the order and complexity of the universe is evidence that the universe was designed. Insofar as the universe is observed to consist of many different parts functioning in harmony to accomplist a purpose, then, we have reason to believe that it was created for that purpose by an intelligent agent.

The inference from the order and complexity of a watch to its being designed is not dependent on knowledge of how watches are made. If we were to stumble across a watch in a natural environment, then we would instantly know that it was designed even without any knowledge of how watches are made or where watches come from. It is therefore no objection to Paley’s argument that we know how watches are made but do not know how universes are made. Order and complexity are together sufficient to support the inference to a designer even without any knowledge at all of the origins of universes. We need not have prior knowledge of how universes are made in order to run Paley’s argument to design.

Nor is it an objection to Paley’s argument that the flaws in the universe, the disorder or failure to accomplish its purpose, count against the claim that it is designed. Even in a watch that sometimes breaks, or runs slow, ordered complexity suggest design; the same must surely hold for the universe.

Not only can we infer from the analogy between the order and complexity of a watch and the order and complexity of the universe that the universe has a designer, we can also infer something about what this designer is like. For the universe is not only ordered and complex in the same way as a watch, but it is so on a much grander scale. The order and complexity of the universe far exceeds that of a watch, and we may therefore infer that the designer of the universe is correspondingly greater than designers of watches.

One objection to this argument is that the analogy between a watch and the universe is too weak to support the inference to a designer of the universe, that there are better alternative analogies available that imply different views of the universe’s origins. Another objection is that arguments from analogy are too limited in the kinds of conclusion that they can support, and so force those who use them into an anthropomorphism that is inconsistent with theism. A further problem is that the principle that ordered complexity implies a designer applies no more to the universe than it does to God, inviting the question Who created God?