"Never apologize for showing feeling. When you do so, you apologize for truth."

- Benjamin Disraeli

I place this at one end of the spectrum. At the other is something my mom used to say - "You control your emotions; your emotions don't control you." I always seem to find myself closer to the first quote though. Or to something one of my favorite authors said,

"But in some cases, it is really more to one's credit to be carried away by an emotion, however unreasonable, which springs from a great love, than to be unmoved." 

Dostoyevsky - The Brothers Karamazov