Final answer:
Bob is most likely experiencing depression, as it is characterized by constant anger and negative thoughts, distinguishing it from normal grief or sadness. Melancholy, often associated with depression, is not one of the seven universal emotions.
Step-by-step explanation:
If Bob is constantly angry and consumed with negative thoughts, it's unlikely that he is experiencing happiness or contentment. Although feelings of anger can sometimes be associated with anxiety, they are more characteristic of intense sadness, pessimism, and the mental slowing mentioned in the context of major depression. Therefore, Bob is most likely experiencing depression. It's important to distinguish depression from normal emotions like grief or sadness because it involves a longer-term pattern of negative thoughts and emotions that can significantly impact a person's life. Treatment options like anti-depressants can help manage the symptoms of major depression. Regarding the seven universal emotions described in the chapter, melancholy is not one of them; rather, it's more associated with depression.