I went indoor rock climbing yesterday. I'm scared of heights. It was terrifying. But, since I did it with guys from work, I forced myself to get to the top mostly because my fear of humiliation outweighed my fear of heights. Similarly, it's been very cold lately in Chicago. Some days I whine when I walk outside. The next day it could be the exact same temperature, and I'm fine. So, obviously, my mental state has a large control over my emotions and behavior. And my question is, how do I conquer these things? Force myself to climb up a mountain? Sit outside in the cold? How do I get control over my mind?