For 
For 20 years during the Sengoku period, Takeda Shingen and Uesugi Kenshin fought a series of hard fought battles. It was during this time that each cultivated a deep respect for one another. When Takeda Shingen died suddenly on the battlefield, Uesugi Kenshin supposedly wept and said, "I have lost my greatest rival, there will never be a greater hero." Our adversaries can be our greatest teachers. As a training partner, it is our duty to bring out the best in our partners. We owe it to them to give them a good hard practice. That doesn't mean be a jerk. It means to push them to become better. If we are too easy they become too complacent and soft. If we are too hard they become bitter and contemptuous. Pushing them to their heights in a positive and productive way enables them to reach their true potential. It is a great honor to be a part of that process. Be a positive force for change so that as C.S. Lewis stated, "All of hell rejoices that I am out of the fight" because I help make others better.