After growing up in the San Francisco bay area of California, Matt joined the U.S. Army where he began his involvement with martial arts as a boxer.

He has recounted this as a breakthrough experience: "I watched Rickson wrestle a room of Judo black belts.

Thornton's training methods seemed better suited to the intense competition of this new MMA arena than highly constrained rules used in martial arts such as Tae Kwon Do, or those which had little or no full force sparring, such as most forms of Kung Fu being practiced at the time.

As a result Thornton was able to attract a few dedicated mixed martial arts competitors, including Randy Couture to the gym, and this led to synergistic improvements in the training methods used.

Now retired, he continues to reference his training under Thornton at Straight Blast Gym as helpful in his growth as a fighter.

Recently Thornton has been applying many of his ideas to the discipline of philosophy, where he champions skepticism, rationality, and the scientific method and opposes faith based belief systems and mysticism.

Beginning in 1998 Matt's seminars were made available as commercial video tapes, which further spread his ideas and reputation in the martial arts community.