Emotion as a way of knowing

All of us experience emotions, however are they limitation for our knowledge. Personally I think there are two types of emotions. You have controlled emotions and uncontrolled emotions. The controlled emotions definitely enriches you way of knowing, while the other type of emotion is most of the time a threat to it. For example if we take the basic emotion of anger. You can experience this emotion in a controlled way or in an uncontrolled way. For example when your teacher told you you had a one for the last test. One option is to freak out. Blame everyone except yourself, and during your rage you can even throw in some windows. When you behave according this option your emotions are definitely uncontrolled, and your level of knowledge is definitely not increasing. However controlling your anger and change this emotion into a positive one. You might increase you level of knowledge. When your teacher told you that you had a one, you can thinking what is the reason for this low mark. Did I study the wrong things, or was my study method not good enough, or were it the nerves? When you do this the chances that you will have another failure will decrease. Of course you can say that when you had no emotion, you would come rationally to the reason for you bad mark. However if you had no emotion, you also would not have the extra motivation to get a high mark the next time. I think that everyone prefers good marks instead of low marks. Thus when you have low marks, most people will get the motivation, which is an emotion, to improve them.