Our evolutionary drive has been to increase our level of comfort. We fled predators, froze in snowstorms, sought shelter from the rain, and hunted and gathered our food. And, today, our lives are surprisingly easy. When we need something we go to the store. But that’s a problem: comfort is actually not good for us. When we forego a few creature comforts, delve more deeply into our own biology, and experience some pain, we’re becoming more human.