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Use the Laws of Detachment and Syllogism to draw a possible conclusion.
If the circus is in town, then there are tents at the fairground.
If there are tents at the fairground, then Paul is working as a night watchman.
The circus is in town.
Using the Law of Syllogism first we can say:
If the circus is in town, then Paul is working as a night watchman.
Now using the Law of Detachment we can conclude:
Paul is working as a night watchman.