Comment on The Second Law of Thermodynamics, and Engines of Cognition

Sun, 21 Mar 2010 00:19:26 GMT

That was a simplified account of what is going on. To include the full system, you would have to include the means by which the Demon recorded the knowledge. However it's recorded, it overwrites the information that was otherwise contained in that recording mechanism (i.e., mutual information with some environment), and this deletion of mutual information is an increase in entropy.

But in such an accounting, you would have three systems, which complicates the scenario. In the example given, the Demon is implicitly taken to include the Demon's recording devices (even if that's his brain). The fact that it has destroyed some relationship between some system (the recording device) and another is represented as higher Demon entropy that retains independence from the Y system. (There are extra states the Demon can have that have nothing to do with Y.)

Did that make any sense?

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