Nor by its title.
Here's a thought. Should you judge a book by its reputation? My mom was concerned when I started reading the Da Vinci Code... but didn't really know why it was bad, just that she had heard it said bad things about Christ. Obviously more info would be best, but if you hear that a book is bad, should you not read it? Or make sure to see for yourself? I would lean towards judging by reputation, but that might be my upbringing. =P
You should seek out more information and then make an informed decision. "A little bit of learning is a dangerous thing..."