There is a savage beast in every man, and when you hand that man a sword or spear and send him forth to war, the beast stirs

There is a savage beast in every man, and when you hand that man a sword or spear and send him forth to war, the beast stirs. The scent of blood is all it takes to wake him.

George R. R. Martin, A Storm of Swords (A Song of Ice and Fire, Book 3)