What does 'that doesn’t mean you might not' mean? While reading the book 'Head First Design Patterns', I came across the next sentences on page 244: So what’s a class adapter and why haven’t we told you about it? Because you need multiple inheritance to implement it, which isn’t possible in Java. But, that doesn’t mean you might not encounter a need for class adapters down the road when using your favorite multiple inheritance language! The last sentence sounds strange for me because I look at it as equivalent to 'But, that doesn’t mean it is possible that you won’t ever encounter...' (what implies 'you will definitely encounter' and looks as a groundless statement), while the other sentence 'But, that doesn’t mean you won’t ever encounter...' would be apt here. Does it mean I haven't made sense of the last sentence? Or is there some logical mistake?