Are you the author of the pdf or do you know the author so that you know for sure? If not then it could be a typo, I'm not sure why that's such a controversial statement?
I peripherally know the author and that was my guess too
Sorry everyone, I was just making a naughty joke about what's probably a mistake in the book. I guess they meant to say a theory of thermodynamics.
This was my take as well, I just meant that you didn't make it up but I'll have to be more clear it seems :)