Two days ago, the boxing world lost its greatest champion, Muhammad Ali. But we lost more than just a great boxer. We lost a dedicated activist, humanitarian and a great American.

Much tribute has been paid to Ali's amazing skill as a boxer. After all, he is the only professional boxer to have held the lineal championship three times and is remembered for winning dozens of matches against top-notch contenders, ranging from rival Joe Frazier to George Foreman. In fact, Ali defeated every heavyweight champion in his era. But Ali did so much more for the world than win championships. Growing up in an era where whites still restricted the freedom of African Americans, Ali was not afraid to provoke those in power. Born as Cassius Marcellus Clay, Jr., he adopted his Muslim name after converting to Islam, denouncing his birth name as a "slave name." A risky move in and of itself, Ali continued to draw ire by joining the Nation of Islam, where he condemned whites for oppressing his people. As a result, he was often the target of much public condemnation and hatred. But Ali persevered, never backing down and serving as an inspiration to African Americans and minorities everywhere. He never hesitated to remind everyone that "I am America. I am the part you won't recognize. But get used to me. Black, confident, cocky; my name, not yours; my religion, not yours; my goals, my own; get used to me."

Perhaps the greatest challenge to Ali's beliefs came in the form of the Vietnam War. Ali showed great courage and determination by refusing to fight a war he viewed as racist and unjust. Risking harsh punishment for rejecting the draft, he did not waver in his conviction. As he put it, "Why should they ask me to put on a uniform and go ten thousand miles from home and drop bombs and bullets on brown people in Vietnam while so-called Negro people in Louisville are treated like dogs and denied simple human rights?" Even if you don't agree that Ali did the right thing, you can't help but admire his integrity and resolve.

However, Ali was indeed punished for rejecting the draft. He was arrested in 1971, and although he did not go to jail for long, he was stripped of all his boxing titles while he appealed the conviction all the way to the Supreme Court. Even though he was acquitted on a technicality, he lost something very valuable to him: Nearly four years of his prime which could have been spent boxing. But Ali showed everyone the strength of his spirit when he made several comebacks shortly thereafter: He fought matches all the way to the championship, winning it in 1974 and again in 1978.

While Ali may not have been undefeated in the ring, he was certainly undefeated in soul and spirit. He was more than just an athlete: He inspired millions of people to stand up for their beliefs, including Martin Luther King, Jr. (King had been reluctant to criticize the Vietnam War before Ali articulated his stance). Truly, Muhammad Ali redefined what it means to be a great athlete as well as what it means to be a great American. And so, we seek to honor his legacy in that respect.