The Oxford English Dictionary defines emotional intelligence as follows:
The capacity to be aware of, control, and express one's emotions, and to handle interpersonal relationships judiciously and empathetically.
Whereas IQ (intelligence quotient) refers to our capacity for intellectual intelligence and logical problem solving, EQ, or emotional quotient, refers to ones capacity for the self-reflective identification of ones emotions, and our ability to manage and express those emotions towards others. It is a reflection of our social skills, and our capacity for managing interpersonal relationships.
Human beings are inherently social creatures. We rely on our emotional intellience to successfully navigate complex social environments and sitations, and is a foundation upon which our capacity for teamwork is built upon. It also serves as the basis for which our ethics, morals, and values are built on. It informs our capacity for empathy, and understanding on the importance of putting the needs of the many before the needs of the few.
Because of our emotional intelligence, we may observe our emotions, rather than be enveloped by them. It allows us to forgive, and to move on from lifes inevitable tragedies and transgressions.