Based on his writings and martial philosophy, Miyamoto Musashi would say that someone with nothing to lose is far more dangerous, though with a critical caveat regarding emotional control.
In Musashi’s view, having "everything to protect" acts as a heavy mental burden that slows a fighter down, whereas letting go of attachment unlocks total commitment.
Why "Everything to Protect" is a Weakness
In his classic treatise, The Book of Five Rings, and his final precepts, Dokkōdō (The Way of Walking Alone), Musashi repeatedly warns against attachment and fear of loss:
• Attachment creates hesitation. When you have everything to protect, your mind splits its focus between attacking the enemy and defending what you value. In a duel, a split-second of hesitation to guard your life or your pride is fatal.
• Fear clouds judgment. Protecting something breeds fear of losing it. Fear makes a fighter predictable, defensive, and reactive rather than proactive.
• The "Water" vs. "Stone" mindset. Musashi taught that a warrior's mind must be like water—fluid, adaptable, and unbound. Clinging to things you want to protect makes your mind rigid and heavy.
Why "Nothing to Lose" is Dangerous
Musashi’s core combat philosophy aligns closely with the mindset of having nothing left to lose:
• Fighting as if already dead. A foundational samurai principle Musashi embodied is entering battle having already accepted your own death. When you have nothing to preserve—no future, no reputation, no survival—you stop negotiating with the outcome and commit 100% to every strike.
• Total freedom of action. Without the fear of loss holding you back, your body and mind move without friction or doubt.
Musashi’s Crucial Caveat: Desperation vs. Detachment
While Musashi would favor the person with nothing to lose, he would make a sharp distinction between desperation and true detachment:
• The trap of desperation. A person with nothing to lose who fights out of blind rage, despair, or recklessness is easily defeated. Musashi wrote that if an opponent can make you angry or emotional, they already control you.
• The ideal warrior. To Musashi, the most dangerous fighter is someone who has chosen to let go of everything—not out of misery, but out of discipline. This person has nothing to lose, yet remains completely calm, observant, and unshakable (Fudōshin, or the "immovable mind").
In short, Musashi would argue that the person fighting to protect everything will hesitate to save what they love, while the person who has let go of everything will strike without holding back.