I started reading "Hagakure," which was written by the samurai Yamamoto Tsunetomo from 1709 to 1716. I don't agree with everything in the book - some of the things Yamamoto-sama says sound crazy to my modern sensibilities, but there's some powerful quotes in here about bushido. Here's some I liked, with some thoughts of my own -
We all want to live. And in large part we make our logic according to what we like. But not having attained our aim and continuing to live is cowardice. This is a thin dangerous line. To die without gaming one's aim is a dog's death and fanaticism. But there is no shame in this. This is the substance of the Way of the Samurai. If by setting one's heart right every morning and evening, one is able to live as though his body were already dead, he pains freedom in the Way. His whole life will be without blame, and he will succeed in his calling.
The first book of philosophy on bushido I read was the Budoshoshinshu. It had a significant impact on my thinking. One of the largest tenets of bushido is keeping awareness of your death in mind when you live. I try to do this, because it gives you a sense of urgency and importance.
A lot of times the principle is misunderstood - the principle is actually make preparations as if you'll live forever, but live this day that you'd be proud if it was your last. Bushido is not about being reckless. It's about keeping awareness of the end with you, and in doing so, living much more.
It's almost paradoxical - the man who is aware of his death, who relinquishes his claim on life, he lives much more fully. The man who is ignorant of his death does not live as much. Death is not something to be afraid of - it's something to be aware of. Being aware of it makes you more alive, and more effective, and more purposeful.
From B.H. Liddel Hart's "Why Don't We Learn From History?"
We learn from history that in every age and every clime the majority of people have resented what seems in retrospect to have been purely matter-of-fact comment on their institutions. We learn too that nothing has aided the persistence of falsehood, and the evils resulting from it, more than the unwillingness of good people to admit the truth when it was disturbing to their comfortable assurance. Always the tendency continues to be shocked by natural comment and to hold certain things too “sacred” to think about.
I can conceive of no finer ideal of a man's life than to face life with clear eyes instead of stumbling through it like a blind man, an imbecile, or a drunkard—which, in a thinking sense, is the common preference. How rarely does one meet anyone whose first reaction to anything is to ask “Is it true?” Yet unless that is a man's natural reaction it shows that truth is not uppermost in his mind, and, unless it is, true progress is unlikely.