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This short story was in a collection by one author.
It concerns one human in bad condition - hungry, and ill - finding a farm where all the work is being done by machines of varying intelligence. The machines are designed for one task each only and speak in a logical fashion to each other. He is passed up the chain of machines to decide what is to be done with this intruder into their ordered system. It becomes clear that the machines have not seen a human for a long time and they probably have all died.
The last sentence is that the most intelligent machine calls the man "Master" and asks for orders.