The correct use of the foregoing table depends entirely upon correct diagnosis. Knowledge of the vertebra to be adjusted for the correction of any disease is useless unless the disease be recognized when met. Diagnosis may be, and usually is, aided by Palpation and Nerve-Tracing, which may be considered as divisions of diagnosis since the subluxation and the tender nerve are evidences (symptoms) of disease. But these two divisions can never wholly take the place of a complete diagnosis which calls to the aid of the examiner _every_ harmless method of ascertaining the patient’s condition. The part may not suffice for the whole. The Chiropractor has an opportunity to become the best of diagnosticians because he has at his command all the usually taught methods and _in addition_ Palpation and Nerve-Tracing, which are especially useful in differential diagnosis. (See “Schedule of Examination.”) The profession is at present lamentably weak in diagnosis and as long as they remain so they will fail to achieve the possible maximum of results from the application of a theory which, _per se_, is applicable to all disease but which is often imperfectly applied in practice. PRACTICE Introduction The ensuing section is intended rather more for the use of the practitioner than for the guidance of the student but may furnish the student a preconception which will prepare him somewhat, before leaving college, to meet the problems of practice. Just as too frequently the young Chiropractor overlooks the fundamental logic of Chiropractic which may be epitomized with the terse command, “Adjust the _cause_,” and considers his practice as requiring him to dabble in every suggested or discovered method of treating _effects_, so, too frequently, the young Chiropractor is prone to consider that his practice consists solely of the adjustment of vertebrae, that he practices a mechanic art rather than a profession; too frequently he overlooks the thousand details which lead to and surround the adjustment and are essential to its success. The practice of Chiropractic involves more than correct technic. It includes the use of a vast fund of knowledge; the constant study of diseases and of patients; the art of controlling and directing others sometimes in their very trivial acts. Successful practice requires a proper setting, proper business methods, and a knowledge of psychology.