…Ultimately all diseases are mental; all are caused by willfulness, that perversion of common sense
that makes us do what we are not supposed to do. This willful perversity is [an] “offense against wisdom”
-Dr. Svoboda from Prakriti: Your Ayurvedic Constitution

It does sound really good, but is it true? All diseases are caused willingly?
Weird. Nietzsche was yapping all about will to power.
The will might be something of an override position; essentially mind over matter.
I can convince myself to go running when my being doesn’t want to, or
I can keep myself from drinking when my body is aching for a beer, or I can
rob a bank even though it makes me very nervous and don’t really need the money.
Thus, it seems like willing can be good or bad depending on the circumstance.
I tend to believe that stress is causing many diseases in the world today.
This stress is manufactured by modern society to a large extent, but also
competitive human nature; over-achieving.
The body is saying, “No! no!, I’m not in the mood’, but the will says, ‘just do it.’
This leads to a disease state. The risk-reward mechanism. Over-thinking
leads to a lack of proper breathing, to lack of oxygen, to disease. Over-exerting
the body in a similar manner.
Money and time are like drugs for the will.
So yes, I agree. In general, all diseases are caused by willfulness.