Gary Michelson's Unconventional Path to Becoming a Billionaire The medical innovator's success didn't come easy, but in this exclusive interview, he shares the values that got him there.

When we think of most billionaires, we imagine founders of software companies in Silicon Valley, hedge-fund mavens or even oil tycoons. Many of them are merely heirs to the billionaires who came before them. Whatever the case, it can be difficult to relate to them. Some of them are far smarter than we'll ever be, while others are born into families we could never have. It makes you wonder whether it's even possible to come from a modest background and become a billionaire if all you know is hard work and passion. Renowned medical innovator Gary Michelson is living proof that it is.

Recently, I had a chance to chat with Michelson, who was once a 17-year-old out on the streets with two dollars to his name. Eventually, after putting himself through college, he began his career as a spinal surgeon, and from there, a thirst for innovation and a big break put him on the path to becoming one of the richest people in the world.

Here's what that unconventional path looked like.

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An Early Interest In Medicine

Michelson's journey to becoming a billionaire started during his childhood, when his interest in medicine and innovation developed. His grandmother, who struggled with a spinal disease, was a big inspiration in his life. Michelson recalls: "The medical part really began with my grandmother, who had syringomyelia. I remember the scene from my childhood when she did not notice that her hand was on fire while cooking at the stove. She said to me, "When you become a doctor, you will fix me.'"

That memory cultivated Michelson's passion for medicine, and the only clear path toward being able to help those people was to become a doctor.

Overcoming Early Challenges

There are challenges and struggles that everyone will face at one point or another in their lives, but what makes certain people stand out from others is how they handle these struggles and apply them to challenges later on. Michelson's parents divorced when he was nine, and he spent much of his life without a father figure. Along with this, he had to put himself through undergraduate and medical school by working multiple jobs. When I ask Michelson about the adversities he faced, he describes that, "There was something about that level of adversity that toughened me up and forced me to grow up very quickly. Later in my life, there were some real battles to be fought, and at least one was a war. I do not think that without that hardening, I would have been able to stand up to those challenges."

The ways he learned to adapt to them eventually helped him prepare for the critical business challenges he would face later in life.

Putting Himself Through School

Many tend to think that billionaires get their start with help from parents and friends. This was far from the truth for Michelson. He told me many of the struggles he faced before he even started his undergraduate degree. "When I was 17, I found myself out on the street with two dollars in my pocket and a small bag of belongings," he recalls. "Those were rough times. I remember bagging groceries and washing cars at a dealership to get just enough money to eat each day."

During his entire time at school, he juggled multiple jobs to pay his tuition and spent most of his free time at the library because he couldn't afford to purchase textbooks. Not to mention, even the dean of his medical school didn't believe in him, remarking that he had never seen anyone successfully graduate while holding a regular job. But Michelson stayed headstrong and believed in what he was doing, and ultimately graduated and began what would become an illustrious career.

Standing Up for Himself

While in medical school, Michelson faced a tough moral situation where he was required to practice surgery on live dogs who weren't treated with painkillers. "On the very first day of that merciless lab, I said, "I will not do that,'" he affirms. "I was told that the lab was compulsory and that if I did not participate, I would be expelled."

Michelson didn't care -- he had a clear moral compass. And he ultimately avoided expulsion after the director of orthopedic surgery at Moffitt Hospital in San Francisco, where he had completed an externship, wrote a compelling letter to the dean. And it's a good thing, because as Michelson tells it, "That summer, a little boy had come in with a condition for which the normal treatment was amputation. I went to the medical library and read for hours, then came back to the person who was running the program with an idea for an operation that had never been done before. They were intrigued and accepted my plan, which saved this boy's leg."

In 2001, Michelson encountered an even bigger problem; he was being sued for $863 million by a Fortune 500 company. "Three years later, on the eve of trial, they came back and offered what they said would be more money than I could spend for the rest of my life," he explains. "But [with the contingency] for them to still take what they wanted and for me to still go away."

Michelson would not settle for the company's long-standing claims that he was a cheat and a fraudster, not for any amount of money. So he stood trial against the company, and sure enough, he ended up winning.

A Commitment to Giving Back

Michelson made a fortune through what really can be attributed to hard work. But with his billionaire status, Michelson doesn't just spend luxuriously; he finds ways to give back. He is the founder and funder of three private charities: the 20MM Foundation, which funds the dissemination of free, peer-reviewed, openly licensed digital textbooks for essential college general-education courses; the Michelson Medical Research Foundation, a $100 million initiative that funds cutting-edge medical research; and the Found Animals Foundation, which provides grants for the rescue and placement of shelter animals. Michelson is also a part of the Giving Pledge, which was started by Bill Gates and Warren Buffet as a mandate for billionaires to donate at least half of their net worth to charitable causes.

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The journey for Michelson to get to this point has been tough, from working multiple jobs to put himself through school to undergoing a lawsuit with a major company. But Michelson stuck to what he believed in and never gave up. Though he is now in a completely different place than he used to be, he clearly hasn't forgotten his roots. Undoubtedly, he has made a fortune for himself, but time and time again he has decided to share that fortune with those who need it most. By doing so, he has gone far beyond just being a billionaire; he has made a significant difference too.