Scott Adams coins a new one:

Suppose we define a creature to have consciousness and free will if it demonstrates the ability to use the external world to reprogram its own brain toward specific ends. By this definition, reading a book in order to change one's mood or gain data would be an example of both consciousness and free will. But a monkey using a stick as a tool to get bugs would be nothing more than eating. The monkey is not trying to become a smarter or happier monkey; he's just feeding his body.

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