Artificial organ almost always preceded by extensive experiments with animals. Initial testing in humans is frequently limited to those either already facing death or who have exhausted every other treatment possibility. Artificial arms and legs, or prosthetics, are intended to restore a degree of normal function to amputees. Mechanical devices that allow amputees to walk again or continue to use two hands have probably been in use since ancient times, the most notable one being the simple peg leg. Since then, the development of artificial limbs has progressed rapidly. New plastics and other materials, such as carbon fiber have allowed artificial limbs
Occult science in medicine of the human being is its divine source (i.e. highest plane of existence) and not the physical body (i.e. lowest plane of existence). This is the recurrent dualistic presentation of the nature of man that is the basis of Hartmann's argument. Theophrastus Paracelsus is portrayed as the father of medicine and given as example of a physician that recognized the sevenfold constitution of man and used this knowledge to treat his patients. The pillars upon which the practice of modern medicine, which is concerned only with the external plane of existence (i.e. the physical world), rests: Psychology is portrayed as