A massive bridge spans a gaping chasm as the sun shimmers and glints in a muddy ribbon of water far below us. I feel very silly when I realize we are at the Rio Grande Gorge Bridge. Parking the car, we venture out onto the magnificent steel and concrete arch. Suddenly, I become acutely aware at the lack of substantial railing between stable ground and dangerous void. My palms immediately begin sweating. Knowing that I am safe, I sit down, hang my head and feet between the bars and try to erase the bridge from my mind. Thousands upon thousands of years of evolution is responsible for the dryness in my mouth and the queasiness in my stomach. I remind myself of the simple fact I have never been scared of heights, but my subconscious isn't fooled. It seems my fear is rooted in the nothingness.