When one says that one likes something, it is always an expression of emotion. It doesn't matter if you say you like a girl or if you say that you like driving. The act of liking is always an emotional act. It has no rational basis.
When you like something very strongly, we say that you have a passion for it. Thus, passionate people are deeply emotional when it comes to their passion.
More importantly however, only those who are capable of being very emotional can be passionate about something.
You can't be passionate without being emotional.
I will consider whether it is important to be passionate in a later post.