Chiropractors simply apply extensive knowledge of functional anatomy and biomechanics to improve a person's spinal and joint functions toward normal. When the spine functions at its full capacity, without malfunction, it allows the nervous system to function without interference or impairment. (This interference can be thought of as "static" or a short in the electrical system.) When the nervous system functions at its full capacity, the biological structures (muscles, organs and tissues) supplied and controlled by the associated nerves also function properly. When all the end organs (structures) of a person's being are functioning properly, obviously, the person achieves maximum health. This is the ultimate goal of chiropractic care. The body can, of itself, ward off sickness and disease without external (assistance) or interference up to the point of the "limitations of matter." It is at the breeching of these "limitations of matter" and only at this point that crisis intervention through pharmaceutics or surgery may be beneficial. Chiropractors are trained to be able to diagnose the patient and recognise when the "limitation of matter" is being reached and can make the appropriate allopathic medical referrals.