Buddhism recognises all of these explanations of disease as valid, but would claim that such causes of disease were themselves manifestations of deeper causes. The Buddhist concept of disease is a multitiered system of causes. Karma makes sense of why two similar people can both spend their lives smoking 40 cigarettes a day and why one dies of lung cancer and the other lives to be a hundred and dies of natural causes. Unless the root cause of negative karma to experience a particular effect exists, the secondary causes cannot function. Whilst karma is virtually impossible to prove to a sceptic, I suggest there is a link between the negative energy created by karma, and the vital force as perceived in homoeopathy, or even a disturbance of the libido as described by Freud.
Buddhist healing involves working with both the primary and the secondary causes.
Many of the methods act upon both and one aim is to restore physical and emotional balance. In common with the system of Chinese medicine, Buddhism recognises that the mechanism of disease is to disturb and imbalance the inner elements, so many healing exercises are aimed at harmonising the elements. The ultimate healing in Buddhism which acts upon primary and secondary causes and also re-establishes equilibrium is to destroy the innate concept we have of the self as being a real and solid entity. By learning to relax our grasping and see through the illusion like ego we gain a state of openness and ease, and physical afflictions can melt away. However, this is not an easy practice and requires considerable instruction.