think of it like this Bruce once wrote something like how martial arts is shattered due to the partiality of all Martial arts like judo only does throws, karate lacks ground work, etc,, so he believed that JKD was the totality of it all so MMA combines throws, kicks, groundwork, kicks, etc.. the only problem it it lacks the spiritual and philosophical aspects of traditional martial arts yet MMA doesnt really combine MA only fighters combine what they like, like Muay thai and BJJ, karate and Judo, But MMA is a sport not a true total martial art, although im pretty sure an MMA artist will be able to defend himself