THIS IS JUST INFORMATION
This book contains just information. All information can be (partially or completely) true or false regardless of where it is found. "Great spiritual master", "enlightened guru", TV, a book, Internet and others are sources of information. None of these and no other source of information can give you (real, true) knowledge.
Knowledge is something you build by experience, using the information you receive. The information itself is not knowledge. To build your own knowledge, you can use information from different sources. Having checked the information out and having experienced it, you can say: I know. Until then you were believing, you did not know.
Belief has an unbreakable connection with doubt (actually it is the same thing but seen from the other side). What you believe as true, you also doubt. When you doubt something, at the same time you also believe it. Also when you believe, you may be questioning and searching until you gain knowledge. When you know, you do not ask, you just know, period.
Therefore do not blindly believe what is written in this book; it is better to find out yourself. You can take advantage of all the information here in any way. For example, you can test it on yourself in order to build your own knowledge. If you are going to blindly believe what is written here, you may suffer as a consequence.
When you believe the information you receive to be your knowledge, you become a slave to the information source. A group of people believing in a so called authority (guru, master, teacher, expert) can be easily manipulated. This was one of the main reasons why (and how) religions, -isms, parties, cults and other organizations, which are controlling people and their life style, have been established and continue to prosper.
In other words, I suggest that you think for yourself. Use the information and treat all "spiritual masters", "recognized authorities", mass media etc. as sources of information only. Then work with the information yourself, not allowing others to manipulate you. Test it yourself, experience it yourself, because if you do not, you will never know, you will just be able to believe.
And to close, let me ask you: Do you believe in God?
Yes?
No?
Why?
So what?