Miyamoto Musashi

Born Shinmen Takezō, Musashi's life reads less like a biography and more like an instruction manual for becoming a certified badass. He started dueling at age 13, because what else is a budding samurai supposed to do with his free time? His 60-odd undefeated duels suggest he was quite good at it, though we suspect his opponents might have disagreed with the outcome.

After achieving peak sword-wielding proficiency, Musashi decided to try his hand at writing, because being the greatest swordsman in Japan wasn't quite enough. His magnum opus, "The Book of Five Rings," is still studied today by everyone from martial artists to business executives. Apparently, the secret to corporate dominance lies in understanding the way of the sword, or at least, the way Musashi thought about it.

While his methods might seem a tad extreme for modern conflict resolution, you can't deny the man's dedication to his craft. He didn't just fight; he philosophized about fighting, making him the original warrior-intellectual, long before anyone thought to combine "bullet points" with "battle plans."