What makes bones great is not that they are difficult to break but that they can be repaired. I wonder if evolution tried out different strengths of bone (and say there's a trade-off between the breakability of the bone and the ability for the bone to be healed quickly). Maybe bones are designed to break, just like some cars are designed to crumple in order to absorb blows.
Life should be designed to break too. Personal philosophies, principles, and opinions should all be designed to handle some level of violent impact. Let them fall apart for a while, and work on a good immune system that can put them back together again (maybe not exactly as they were before, maybe in a slightly better way). One of the main catalysts in the evolution of life has been several breaking points where life was put under severe violence and pain, and changes had to be made quick. Things like the eye and the thumb were born in relatively short periods of difficulty. Actually, I just made that up but I'm sure something like that is the case. Right?
That's why, if you're religious, you shouldn't always necessarily pray for health and safety. Sometimes pray for challenge, pain, and loss. That is, if you want to improve, and live a life worth living.
Mmm... I love tea. The "launch early, fail early, iterate often" approach is a "designed to break" philosophy. If you make the bones too strong, it might be too difficult to change them when they need to be modified. Maybe you built the hand and accidentally only put 4 fingers on it. Your morals and ethical code should be written in pencil.
A lot of people don't drink or don't take risks because they don't like it when things are out of their immediate control. If you let things break, it's like allowing things to pass through the permeable membrane of your life and personality. Imagine that you're a balloon. You have air inside. There's also air outside. Do you want to let some of that air in? Which air is better? A life designed to break is betting that there's better air outside the balloon than inside. It's an optimistic view of the world to believe that there are things outside the balloon worth letting in. A pessimist would insist on sticking only with what they've got.
This goes along with a saying I think sounds counter-intuitive but might have something to it: live and don't learn. I don't mean that you shouldn't ever change behavior and thoughts in response to things that have happened. I just mean, don't set the new behaviors and thoughts in stone... just take them as the most recent version of behaviors and thoughts... and let those in turn get broken, reset, etc.