People sometimes behave irrationally because of their emotional feelings. A perfect example in this case would be love relationships. Why do people involved in love relationships behave sometimes strangely? Why do they keep changing their minds? Why do such people do things they once said they would have never done? Why do these people keep repeating their "mistakes" over and over? And finally, why do these people sometimes seem to enjoy suffering although under normal circumstances they are not necessarily masochists? A person who has not experienced love would be hard pressed to answer these questions. Without experiencing the feeling of love in an emotional way, we can never understand it. For a person who has experienced love, none of the questions I am asking here would seem strange. In other words, certain things cannot be understood without emotion. The importance of emotion in understanding things can be illustrated in the following examples. Let us say that someone tells us that she has been cheated. We may tell them that we understand her but in reality we do not feel what she does. We only have empathy for her and can visualize what happened to her in our minds. But we cannot feel what it means to be cheated without experiencing it by ourselves and sensing all the emotions involved in it. The same...

His tales of living in dangerous places and experiencing extremely hard times may invoke a sense of empathy and visual imaginations (which may be far from reality) in us, but we cannot understand the soldier's experiences until we experience the war itself. Neither the experience of a cheated woman nor that of a war veteran can be understood without emotionally feeling their real-life experiences.
In short, emotion, just like other ways of knowing things, can be limiting but nevertheless essential for gaining knowledge. Emotion shapes our thinking, influences our behavior, and encourages us to learn. And there are certain things in life that can never be understood or learnt without emotionally feeling them. For this reason, I argue that emotion is not only a way of learning but is essential in the learning process.

References

Diploma Program, Theory of Knowledge: Guide. International Baccalaureate Organization. Cardiff, Wales, Great Britain. 2006

Solomon, Robert, C. "On Emotions as Judgments." American Philosophical Quarterly, 25/2 (1988): 183-191.

"Emotion," Stanford Encyclopedia of Philosophy. 14 January 2010. Web 21 June 2011, from http://plato.stanford.edu/entries/emotion/#9.