The Bill Hetzel Principle

After taking a practice test for ISTQB certification I came across a question asking where 'testing must be planned' is stated and the Bill Hetzel Principle was the answer.  I wasn't sure what it was, and since this was a chapter 1 quiz I tried to find where it was mentioned in ISTQB book with no success, so I decided to do some research.  So I found that Bill Hetzel wrote a book on software testing called 'The Complete Guide to Software Testing' in 1988, and it is still considered a good one from what I can tell.
While I haven't been able to get access to it I found that some of his main testing principles are:

• Complete testing is not possible
• Testing is creative and difficult
• An important reason for testing is to prevent defects
• Testing is risk based
• Testing must be planned
• Testing requires independence

Then after looking at this I realized that all of these are mentioned in some way or another throughout the first chapter of the ISTQB book, it just doesn't mention Bill Hetzel by name.  For instance the principle of 'Complete testing is impossible' can be found as one of the testing principles.
Testing must be planned can be found in section 1.2 'What is Testing'
Testing requires independence can be found as one of the code of ethics, and can be found (more or less) along with the remaining principles in section 1.5 The Psychology of Testing.
The principles of 'Testing is creative and difficult', 'An important reason for testing is preventing errors', and 'testing is risk-based' may not necessarily be found word for word in the book, but some of the stuff the book talks about in CH 1 is mostly the same basic principle.