I'm reading a book by Max Wideman at the moment: A Framework for Project and Program Management Integration.
I respect Max's work and experience and his contribution to project management, and I particularly admire his view that project management is not a profession. If you want to characterise it, I suppose it is more like a craft than anything else; just like general management, in fact, a craft with a collection of practices.
Why I admire this view is that Max was one of the instigators of the PMBoK. The 'BoK' was developed in a forlorn attempt to demonstrate that project management is a 'profession'. Of course, a 'profession' has a 'body of knowledge'. The Guide to the PMBoK demonstrates that. Does it not?
If your 'body of knowledge' can be encompassed in a single book then there's not much to it, in my view. Compare this single book to the contents of a law library, and its depth of precedent, or medicine, similarly. A 'body of knowledge' cannot be captured in a single volume, or even in a whole bunch of volumes, but is dispersed across the history and activity of an entire profession's intellectual output; coming to grips with this is the point of professional practice.
So, in documenting a 'guide to a body of knowledge'; project management demonstrates that it is the very opposite of what it seeks: to be regarded as a profession.
That's not to decry the value of project management: of that it has plenty, but I'm sceptical that it has much discrete knowledge to offer society beyond its collection of practices.