Abductive arguments often postulate unobserved entities.
>>> abductive argument

Paley’s two abductive arguments can be summarized:

1. The watch is intricate and well suited to measuring time.
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Therefore, the watch was created by intelligent design.

2. Organisms are intricate and well suited to the tasks of survival and reproduction.
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Therefore, organisms were created by intelligent design.

The analogy between these two abductive arguments makes a strong argument for intelligent design.