The People's Common Sense Medical Adviser In Plain English, Or, Medicine Simplified. By R.V. Pierce, M.D. INTRODUCTORY WORDS. Health and disease are physical conditions upon which pleasure and pain, success and failure, depend. Every individual gain increases public gain. Upon the health of its people is based the prosperity of a nation; by it every value is increased, every joy enhanced. Life is incomplete without the enjoyment of healthy organs and faculties, for these give rise to the delightful sensations of existence. Health is essential to the accomplishment of every purpose; while sickness thwarts the best intentions and loftiest aims. We are continually deciding upon those conditions which are either the source of joy and happiness or which occasion pain and disease.