Hey hubert,
I logged in specifically to tell you this.
That is NOT a purpose.
Your purpose should be simply specific, so to say.
Make it related to the book.
If it's about physics, say something about learning concepts in physics. Give yourself a specific reason to go into the book and get information out of it, without saying it that generally. Some books may have a similar purpose, but you shouldn't have the same purpose for all of them.
And you don't have to follow what Paul says EXACTLY. It's a flexible course, change something to make it your own.
-JackTuff13